!!$ 
!!$              Parallel Sparse BLAS  version 3.0
!!$    (C) Copyright 2006, 2007, 2008, 2009, 2010
!!$                       Salvatore Filippone    University of Rome Tor Vergata
!!$                       Alfredo Buttari        CNRS-IRIT, Toulouse
!!$ 
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!!$  
! File: psb_znrmi.f90
!
! Function: psb_znrmi
!    Forms the approximated norm of a sparse matrix,                           
!
!    normi := max(abs(sum(A(i,j))))                                              
!
! Arguments:
!    a      -  type(psb_dspmat_type).   The sparse matrix containing A.
!    desc_a -  type(psb_desc_type).     The communication descriptor.
!    info   -  integer.                   Return code
!
function psb_znrmi(a,desc_a,info)  
  use psb_descriptor_type
  use psb_serial_mod
  use psb_check_mod
  use psb_error_mod
  use psb_penv_mod
  use psb_mat_mod
  implicit none

  type(psb_zspmat_type), intent(in)   :: a
  integer, intent(out)                :: info
  type(psb_desc_type), intent(in)     :: desc_a
  real(psb_dpk_)                    :: psb_znrmi

  ! locals
  integer                  :: ictxt, np, me,&
       & err_act, n, iia, jja, ia, ja, mdim, ndim, m
  real(psb_dpk_)         :: nrmi
  character(len=20)        :: name, ch_err

  name='psb_znrmi'
  if(psb_get_errstatus() /= 0) return 
  info=psb_success_
  call psb_erractionsave(err_act)

  ictxt=desc_a%get_context()

  call psb_info(ictxt, me, np)
  if (np == -1) then
    info = psb_err_context_error_
    call psb_errpush(info,name)
    goto 9999
  endif

  ia = 1
  ja = 1
  m = desc_a%get_global_rows()
  n = desc_a%get_global_cols()

  call psb_chkmat(m,n,ia,ja,desc_a,info,iia,jja)
  if(info /= psb_success_) then
    info=psb_err_from_subroutine_
    ch_err='psb_chkmat'
    call psb_errpush(info,name,a_err=ch_err)
    goto 9999
  end if

  if ((iia /= 1).or.(jja /= 1)) then
    info=psb_err_ix_n1_iy_n1_unsupported_
    call psb_errpush(info,name)
    goto 9999
  end if

  if ((m /= 0).and.(n /= 0)) then
    nrmi = a%csnmi()
    if(info /= psb_success_) then
      info=psb_err_from_subroutine_
      ch_err='psb_csnmi'
      call psb_errpush(info,name,a_err=ch_err)
      goto 9999
    end if
  else
    nrmi = 0.d0
  end if
  ! compute global max
  call psb_amx(ictxt, nrmi)

  psb_znrmi = nrmi

  call psb_erractionrestore(err_act)
  return  

9999 continue
  call psb_erractionrestore(err_act)

  if (err_act == psb_act_abort_) then
    call psb_error(ictxt)
    return
  end if
  return
end function psb_znrmi