psblas3/base/modules/psi_reduce_mod.F90

module psi_reduce_mod
  use psi_penv_mod
  interface psb_max
    module procedure psb_imaxs, psb_imaxv, psb_imaxm,&
         & psb_smaxs, psb_smaxv, psb_smaxm,&
         & psb_dmaxs, psb_dmaxv, psb_dmaxm
  end interface
#if !defined(LONG_INTEGERS)
  interface psb_max 
    module procedure psb_i8maxs, psb_i8maxv, psb_i8maxm
  end interface
#endif

  interface psb_min
    module procedure psb_imins, psb_iminv, psb_iminm,&
         & psb_smins, psb_sminv, psb_sminm,&
         & psb_dmins, psb_dminv, psb_dminm
  end interface
#if !defined(LONG_INTEGERS)
  interface psb_min
    module procedure psb_i8mins, psb_i8minv, psb_i8minm
  end interface
#endif


  interface psb_amx
    module procedure psb_iamxs, psb_iamxv, psb_iamxm,&
         & psb_samxs, psb_samxv, psb_samxm,&
         & psb_camxs, psb_camxv, psb_camxm,&
         & psb_damxs, psb_damxv, psb_damxm,&
         & psb_zamxs, psb_zamxv, psb_zamxm
  end interface
#if !defined(LONG_INTEGERS)
  interface psb_amx 
    module procedure psb_i8amxs, psb_i8amxv, psb_i8amxm
  end interface
#endif

  interface psb_amn
    module procedure psb_iamns, psb_iamnv, psb_iamnm,&
         & psb_samns, psb_samnv, psb_samnm,&
         & psb_camns, psb_camnv, psb_camnm,&
         & psb_damns, psb_damnv, psb_damnm,&
         & psb_zamns, psb_zamnv, psb_zamnm
  end interface
#if !defined(LONG_INTEGERS)
  interface psb_amn 
    module procedure psb_i8amns, psb_i8amnv, psb_i8amnm
  end interface
#endif


  interface psb_sum
    module procedure psb_isums, psb_isumv, psb_isumm,&
         & psb_ssums, psb_ssumv, psb_ssumm,&
         & psb_csums, psb_csumv, psb_csumm,&
         & psb_dsums, psb_dsumv, psb_dsumm,&
         & psb_zsums, psb_zsumv, psb_zsumm
  end interface
#if defined(SHORT_INTEGERS)
  interface psb_sum
    module procedure psb_i2sums, psb_i2sumv, psb_i2summ
  end interface psb_sum
#endif
#if !defined(LONG_INTEGERS)
  interface psb_sum
    module procedure psb_i8sums, psb_i8sumv, psb_i8summ
  end interface
#endif


  interface psb_nrm2
    module procedure psb_s_nrm2s, psb_s_nrm2v,&
         & psb_d_nrm2s, psb_d_nrm2v
  end interface


contains 

  ! !!!!!!!!!!!!!!!!!!!!!!
  !
  ! Reduction operations
  !
  ! !!!!!!!!!!!!!!!!!!!!!!


  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  !
  !  MAX
  !
  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  subroutine psb_imaxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_, dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,psb_mpi_integer,mpi_max,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,psb_mpi_integer,mpi_max,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_imaxs

  subroutine psb_imaxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_imaxv

  subroutine psb_imaxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_imaxm

#if !defined(LONG_INTEGERS)
  subroutine psb_i8maxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) ::  dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_integer8,mpi_max,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_integer8,mpi_max,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_i8maxs

  subroutine psb_i8maxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8maxv

  subroutine psb_i8maxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8maxm

#endif



  subroutine psb_smaxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_real,mpi_max,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_real,mpi_max,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_smaxs

  subroutine psb_smaxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_smaxv

  subroutine psb_smaxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_smaxm

  subroutine psb_dmaxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_precision,mpi_max,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_precision,mpi_max,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_dmaxs

  subroutine psb_dmaxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,&
           & mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_dmaxv

  subroutine psb_dmaxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,mpi_max,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_max,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_max,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_dmaxm


  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  !
  !  MIN
  !
  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  subroutine psb_imins(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_, dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,psb_mpi_integer,mpi_min,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,psb_mpi_integer,mpi_min,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_imins

  subroutine psb_iminv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_iminv

  subroutine psb_iminm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_iminm

#if !defined(LONG_INTEGERS)
  subroutine psb_i8mins(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) ::  dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_integer8,mpi_min,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_integer8,mpi_min,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_i8mins

  subroutine psb_i8minv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8minv

  subroutine psb_i8minm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8minm

#endif



  subroutine psb_smins(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_real,mpi_min,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_real,mpi_min,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_smins

  subroutine psb_sminv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_sminv

  subroutine psb_sminm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_sminm

  subroutine psb_dmins(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_precision,mpi_min,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_precision,mpi_min,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_dmins

  subroutine psb_dminv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,&
           & mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_dminv

  subroutine psb_dminm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,mpi_min,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_min,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_min,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_dminm


  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  !
  !  AMX: maximum absolute value
  !
  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!


  subroutine psb_iamxs(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,psb_mpi_integer,mpi_iamx_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,psb_mpi_integer,mpi_iamx_op,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_iamxs

  subroutine psb_iamxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_iamx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_iamx_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_iamx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_iamxv

  subroutine psb_iamxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_iamx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_iamx_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_iamx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_iamxm


#if !defined(LONG_INTEGERS)
  subroutine psb_i8amxs(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_integer8,mpi_i8amx_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_integer8,mpi_i8amx_op,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_i8amxs

  subroutine psb_i8amxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_i8amx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_i8amx_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_i8amx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8amxv

  subroutine psb_i8amxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_i8amx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_i8amx_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_i8amx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8amxm

#endif



  subroutine psb_samxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_real,mpi_samx_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_real,mpi_samx_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_samxs

  subroutine psb_samxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_samx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_samx_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_samx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_samxv

  subroutine psb_samxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_samx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_samx_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_samx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_samxm

  subroutine psb_damxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_precision,mpi_damx_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_precision,mpi_damx_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_damxs

  subroutine psb_damxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,&
           & mpi_damx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_damx_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_damx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_damxv

  subroutine psb_damxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,mpi_damx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_damx_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_damx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_damxm


  subroutine psb_camxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_complex,mpi_camx_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_complex,mpi_camx_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_camxs

  subroutine psb_camxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_complex,mpi_camx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_complex,mpi_camx_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_complex,mpi_camx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_camxv

  subroutine psb_camxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_complex,mpi_camx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_complex,mpi_camx_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_complex,mpi_camx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_camxm

  subroutine psb_zamxs(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_complex,mpi_zamx_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_complex,mpi_zamx_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_zamxs

  subroutine psb_zamxv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_complex,&
           & mpi_zamx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_complex,mpi_zamx_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_complex,mpi_zamx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_zamxv

  subroutine psb_zamxm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_complex,mpi_zamx_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_complex,mpi_zamx_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_complex,mpi_zamx_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_zamxm



  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  !
  !  AMN: minimum absolute value
  !
  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  subroutine psb_iamns(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,psb_mpi_integer,mpi_iamn_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,psb_mpi_integer,mpi_iamn_op,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_iamns

  subroutine psb_iamnv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_iamn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_iamn_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_iamn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_iamnv

  subroutine psb_iamnm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_iamn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_iamn_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_iamn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_iamnm


#if !defined(LONG_INTEGERS)
  subroutine psb_i8amns(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_integer8,mpi_i8amn_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_integer8,mpi_i8amn_op,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_i8amns

  subroutine psb_i8amnv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_i8amn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_i8amn_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_i8amn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8amnv

  subroutine psb_i8amnm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_i8amn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_i8amn_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_i8amn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8amnm

#endif



  subroutine psb_samns(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_real,mpi_samn_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_real,mpi_samn_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_samns

  subroutine psb_samnv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_samn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_samn_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_samn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_samnv

  subroutine psb_samnm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_samn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_samn_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_samn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_samnm

  subroutine psb_damns(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_precision,mpi_damn_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_precision,mpi_damn_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_damns

  subroutine psb_damnv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,&
           & mpi_damn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_damn_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_damn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_damnv

  subroutine psb_damnm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,mpi_damn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_damn_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_damn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_damnm


  subroutine psb_camns(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_complex,mpi_camn_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_complex,mpi_camn_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_camns

  subroutine psb_camnv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_complex,mpi_camn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_complex,mpi_camn_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_complex,mpi_camn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_camnv

  subroutine psb_camnm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_complex,mpi_camn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_complex,mpi_camn_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_complex,mpi_camn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_camnm

  subroutine psb_zamns(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_complex,mpi_zamn_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_complex,mpi_zamn_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_zamns

  subroutine psb_zamnv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_complex,&
           & mpi_zamn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_complex,mpi_zamn_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_complex,mpi_zamn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_zamnv

  subroutine psb_zamnm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_complex,mpi_zamn_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_complex,mpi_zamn_op,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_complex,mpi_zamn_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_zamnm


  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
  !
  !  SUM
  !
  ! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  subroutine psb_isums(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,psb_mpi_integer,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,psb_mpi_integer,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_isums

  subroutine psb_isumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_isumv

  subroutine psb_isumm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_ipk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_ipk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & psb_mpi_integer,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),psb_mpi_integer,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),psb_mpi_integer,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_isumm


#if defined(SHORT_INTEGERS)
  subroutine psb_i2sums(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(2), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(2) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_integer2,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_integer2,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_i2sums

  subroutine psb_i2sumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(2), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(2), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer2,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer2,mpi_sum,root_,ictxt,info)
      else
        call mpi_reduce(dat,dat_,size(dat),mpi_integer2,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i2sumv

  subroutine psb_i2summ(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(2), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(2), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer2,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer2,mpi_sum,root_,ictxt,info)
      else
        call mpi_reduce(dat,dat_,size(dat),mpi_integer2,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i2summ

#endif


#if !defined(LONG_INTEGERS)
  subroutine psb_i8sums(ictxt,dat,root)

#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_) :: dat_
    integer(psb_ipk_) :: iam, np, info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_integer8,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_integer8,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif

#endif    
  end subroutine psb_i8sums

  subroutine psb_i8sumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8sumv

  subroutine psb_i8summ(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    integer(psb_long_int_k_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    integer(psb_long_int_k_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_=dat
      if (info == psb_success_) call mpi_allreduce(dat_,dat,size(dat),&
           & mpi_integer8,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_=dat
        call mpi_reduce(dat_,dat,size(dat),mpi_integer8,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_integer8,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_i8summ

#endif



  subroutine psb_ssums(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_real,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_real,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_ssums

  subroutine psb_ssumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_ssumv

  subroutine psb_ssumm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_ssumm

  subroutine psb_dsums(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_precision,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_precision,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_dsums

  subroutine psb_dsumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,&
           & mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_dsumv

  subroutine psb_dsumm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_dsumm


  subroutine psb_csums(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_complex,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_complex,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_csums

  subroutine psb_csumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_complex,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_complex,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_complex,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_csumv

  subroutine psb_csumm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_spk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_spk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_complex,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_complex,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_complex,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_csumm

  subroutine psb_zsums(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_complex,mpi_sum,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_complex,mpi_sum,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_zsums

  subroutine psb_zsumv(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_complex,&
           & mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_complex,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_complex,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_zsumv

  subroutine psb_zsumm(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    complex(psb_dpk_), intent(inout)  :: dat(:,:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    complex(psb_dpk_), allocatable :: dat_(:,:)
    integer(psb_ipk_) :: iam, np,  info

#if !defined(SERIAL_MPI)

    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat,1),size(dat,2),dat_,info)
      dat_ = dat
      if (info == psb_success_)&
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_complex,mpi_sum,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat,1),size(dat,2),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_complex,mpi_sum,root_,ictxt,info)
      else
        call psb_realloc(1,1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_complex,mpi_sum,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_zsumm

  ! !!!!!!!!!!!!
  !
  ! Norm 2
  !
  ! !!!!!!!!!!!!
  subroutine psb_s_nrm2s(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)            :: ictxt
    real(psb_spk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional  :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_real,mpi_snrm2_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_real,mpi_snrm2_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_s_nrm2s

  subroutine psb_d_nrm2s(ictxt,dat,root)
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)            :: ictxt
    real(psb_dpk_), intent(inout)  :: dat
    integer(psb_ipk_), intent(in), optional  :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_) :: dat_
    integer(psb_ipk_) :: iam, np, info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call mpi_allreduce(dat,dat_,1,mpi_double_precision,mpi_dnrm2_op,ictxt,info)
      dat = dat_
    else
      call mpi_reduce(dat,dat_,1,mpi_double_precision,mpi_dnrm2_op,root_,ictxt,info)
      dat = dat_
    endif
#endif    
  end subroutine psb_d_nrm2s

  subroutine psb_s_nrm2v(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)              :: ictxt
    real(psb_spk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional    :: root
    integer(psb_ipk_) :: root_
    real(psb_spk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_real,&
           & mpi_snrm2_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_real,&
             & mpi_snrm2_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_real,&
             & mpi_snrm2_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_s_nrm2v

  subroutine psb_d_nrm2v(ictxt,dat,root)
    use psb_realloc_mod
#ifdef MPI_MOD
    use mpi
#endif
    implicit none 
#ifdef MPI_H
    include 'mpif.h'
#endif
    integer(psb_ipk_), intent(in)            :: ictxt
    real(psb_dpk_), intent(inout)  :: dat(:)
    integer(psb_ipk_), intent(in), optional  :: root
    integer(psb_ipk_) :: root_
    real(psb_dpk_), allocatable :: dat_(:)
    integer(psb_ipk_) :: iam, np,  info


#if !defined(SERIAL_MPI)
    call psb_info(ictxt,iam,np)

    if (present(root)) then 
      root_ = root
    else
      root_ = -1
    endif
    if (root_ == -1) then 
      call psb_realloc(size(dat),dat_,info)
      dat_ = dat
      if (info == psb_success_) &
           & call mpi_allreduce(dat_,dat,size(dat),mpi_double_precision,&
           & mpi_dnrm2_op,ictxt,info)
    else
      if (iam == root_) then 
        call psb_realloc(size(dat),dat_,info)
        dat_ = dat
        call mpi_reduce(dat_,dat,size(dat),mpi_double_precision,&
             & mpi_dnrm2_op,root_,ictxt,info)
      else
        call psb_realloc(1,dat_,info)
        call mpi_reduce(dat,dat_,size(dat),mpi_double_precision,&
             & mpi_dnrm2_op,root_,ictxt,info)
      end if
    endif
#endif    
  end subroutine psb_d_nrm2v


end module psi_reduce_mod