psblas3/prec/impl/psb_sprecinit.f90

!   
!                Parallel Sparse BLAS  version 3.5
!      (C) Copyright 2006-2018
!        Salvatore Filippone    
!        Alfredo Buttari      
!   
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!   
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!   
!    
subroutine psb_sprecinit(p,ptype,info)

  use psb_base_mod
  use psb_s_prec_type, psb_protect_name => psb_sprecinit
  use psb_s_nullprec, only : psb_s_null_prec_type
  use psb_s_diagprec, only : psb_s_diag_prec_type
  use psb_s_bjacprec, only : psb_s_bjac_prec_type
  implicit none
  class(psb_sprec_type), intent(inout)   :: p
  character(len=*), intent(in)           :: ptype
  integer(psb_ipk_), intent(out)         :: info

  info = psb_success_

  if (allocated(p%prec) ) then
    call p%prec%free(info)
    if (info == psb_success_) deallocate(p%prec,stat=info) 
    if (info /= psb_success_) return
  end if
  
  select case(psb_toupper(ptype(1:len_trim(ptype))))
  case ('NONE','NOPREC') 
    
    allocate(psb_s_null_prec_type :: p%prec, stat=info)       
    
  case ('DIAG')
    allocate(psb_s_diag_prec_type :: p%prec, stat=info)       
    
  case ('BJAC') 
    allocate(psb_s_bjac_prec_type :: p%prec, stat=info)       
    
  case default
    write(psb_err_unit,*) 'Unknown preconditioner type request "',ptype,'"'
    info = psb_err_pivot_too_small_
    
  end select
  if (info == psb_success_)  call p%prec%precinit(info)
  
end subroutine psb_sprecinit