MLPREC: merged changes from Daniela of 2008/01/18, minor doc fixes.

mlprec/mld_das_aply.f90

@@ -120,7 +120,7 @@ subroutine mld_das_aply(alpha,prec,x,beta,y,desc_data,trans,work,info)
       call mld_bjac_aply(alpha,prec,x,beta,y,desc_data,trans_,work,info)
       if(info /= 0) then
         info=4010
-        ch_err='psb_bjacaply'
+        ch_err='psb_bjac_aply'
         goto 9999
       end if
 

mlprec/mld_dbaseprec_bld.f90

@@ -39,20 +39,19 @@
 ! Subroutine: mld_dbaseprc_bld
 ! Version:    real
 !
-!  This routine builds the 'base preconditioner' corresponding to a certain level 
-!  of a multilevel preconditioner, according to the requirements made by the 
-!  user through mld_dprecinit and mld_dprecset (for details on the preconditioner
-!  data structure see its description in mld_prec_type.f90). 
+!  This routine builds a 'base preconditioner' related to a matrix A.
+!  In a multilevel framework, it is called by mld_mlprec_bld to build the
+!  base preconditioner at each level.
 !
-!  The level at which the base preconditioner is built is identified in the
-!  call to mld_dbaseprec_bld made by mld_dprec_bld. For one-level preconditioners,
-!  the 'base preconditioner' is the preconditioner itself.
+!  Details on the base preconditioner to be built are stored in the iprcparm
+!  field of the preconditioner data structure (for a description of this
+!  structure see mld_prec_type.f90).
 !    
 !
 ! Arguments:
 !    a       -  type(psb_dspmat_type).
 !               The sparse matrix structure containing the local part of the
-!               matrix to be preconditioned.
+!               matrix A to be preconditioned.
 !    desc_a  -  type(psb_desc_type), input.
 !               The communication descriptor of a.
 !    p       -  type(mld_dbaseprec_type), input/output.

mlprec/mld_dbjac_aply.f90

@@ -66,7 +66,7 @@
 !     preconditioner). Here K^(-1) denotes the iteration matrix of the
 !     block-Jacobi solver, op(K^(-1)) = K^(-1), alpha = 1 and beta = 0.
 !
-!  3. Solution, through      the LU factorization, of a linear system
+!  3. Solution, through the LU factorization, of a linear system
 !
 !                                    A*Y = X,
 !
@@ -77,7 +77,7 @@
 !     a linear system
 !                                    A*Y = X,
 !
-!        replicated on the processes. Here K = L*U = A or K = L*U ~ A,      op(K^(-1)) =
+!     replicated on the processes. Here K = L*U = A or K = L*U ~ A, op(K^(-1)) =
 !     K^(-1), alpha = 1 and beta = 0.
 !
 !  The block-Jacobi preconditioner or solver and the L and U factors of the LU

mlprec/mld_dmlprec_bld.f90

@@ -40,7 +40,9 @@
 ! Version:    real
 !
 !  This routine builds the base preconditioner corresponding to the current
-!  level of the multilevel preconditioner.
+!  level of the multilevel preconditioner. The routine first builds the
+!  (coarse) matrix associated to the current level from the (fine) matrix
+!  associated to the previous level, then builds the related base preconditioner.
 !
 ! 
 ! Arguments:

mlprec/mld_prec_type.f90

@@ -236,7 +236,7 @@ module mld_prec_type
   ! Legal values for entry: mld_sub_ren_
   !
   integer, parameter :: mld_renum_none_=0, mld_renum_glb_=1, mld_renum_gps_=2
-  ! For the time being we are disabling GPS renumbering...
+  ! For the time being we are disabling GPS renumbering.
   integer, parameter :: mld_max_renum_=1
   !
   ! Legal values for entry: mld_ml_type_

mlprec/mld_zas_aply.f90

@@ -113,18 +113,21 @@ subroutine mld_zas_aply(alpha,prec,x,beta,y,desc_data,trans,work,info)
     ! Additive Schwarz preconditioner
     !
 
-    if (prec%iprcparm(mld_n_ovr_)==0) then
+    if ((prec%iprcparm(mld_n_ovr_)==0).or.(np==1)) then
       ! 
-      ! shortcut: this fixes performance for RAS(0) == BJA
+      ! Shortcut: this fixes performance for RAS(0) == BJA
       !
       call mld_bjac_aply(alpha,prec,x,beta,y,desc_data,trans_,work,info)
       if(info /= 0) then
         info=4010
-        ch_err='psb_bjacaply'
+        ch_err='psb_bjac_aply'
         goto 9999
       end if
 
     else
+      !
+      ! Overlap > 0
+      !
 
       n_row  = psb_cd_get_local_rows(prec%desc_data)
       n_col  = psb_cd_get_local_cols(prec%desc_data)
@@ -248,7 +251,6 @@ subroutine mld_zas_aply(alpha,prec,x,beta,y,desc_data,trans,work,info)
         end select
 
       case('T','C')
-
         !
         ! With transpose, we have to do it here
         ! 
@@ -261,7 +263,7 @@ subroutine mld_zas_aply(alpha,prec,x,beta,y,desc_data,trans,work,info)
 
         case(psb_sum_) 
           !
-          ! Transpose of sum is halo
+          ! The transpose of sum is halo
           !
           call psb_halo(tx,prec%desc_data,info,work=aux,data=psb_comm_ext_)
           if(info /=0) then
@@ -295,7 +297,6 @@ subroutine mld_zas_aply(alpha,prec,x,beta,y,desc_data,trans,work,info)
           goto 9999
         end select
 
-
         !
         ! If required, reorder tx according to the row/column permutation of the
         ! local extended matrix, stored into the permutation vector prec%perm

mlprec/mld_zbaseprec_bld.f90

@@ -39,20 +39,19 @@
 ! Subroutine: mld_zbaseprc_bld
 ! Version:    complex
 !
-!  This routine builds the 'base preconditioner' corresponding to a certain level 
-!  of a multilevel preconditioner, according to the requirements made by the 
-!  user through mld_dprecinit and mld_dprecset (for details on the preconditioner
-!  data structure see its description in mld_prec_type.f90). 
+!  This routine builds a 'base preconditioner' related to a matrix A.
+!  In a multilevel framework, it is called by mld_mlprec_bld to build the
+!  base preconditioner at each level.
 !
-!  The level at which the base preconditioner is built is identified in the
-!  call to mld_dbaseprec_bld made by mld_dprec_bld. For one-level preconditioners,
-!  the 'base preconditioner' is the preconditioner itself.
+!  Details on the base preconditioner to be built are stored in the iprcparm
+!  field of the preconditioner data structure (for a description of this
+!  structure see mld_prec_type.f90).
 !    
 !
 ! Arguments:
 !    a       -  type(psb_zspmat_type).
 !               The sparse matrix structure containing the local part of the
-!               matrix to be preconditioned.
+!               matrix A to be preconditioned.
 !    desc_a  -  type(psb_desc_type), input.
 !               The communication descriptor of a.
 !    p       -  type(mld_zbaseprec_type), input/output.

mlprec/mld_zbjac_aply.f90

@@ -66,7 +66,7 @@
 !     preconditioner). Here K^(-1) denotes the iteration matrix of the
 !     block-Jacobi solver, op(K^(-1)) = K^(-1), alpha = 1 and beta = 0.
 !
-!  3. Solution, through      the LU factorization, of a linear system
+!  3. Solution, through the LU factorization, of a linear system
 !
 !                                    A*Y = X,
 !
@@ -77,7 +77,7 @@
 !     a linear system
 !                                    A*Y = X,
 !
-!        replicated on the processes. Here K = L*U = A or K = L*U ~ A,      op(K^(-1)) =
+!     replicated on the processes. Here K = L*U = A or K = L*U ~ A, op(K^(-1)) =
 !     K^(-1), alpha = 1 and beta = 0.
 !
 !  The block-Jacobi preconditioner or solver and the L and U factors of the LU

mlprec/mld_zmlprec_bld.f90

@@ -40,7 +40,9 @@
 ! Version:    complex
 !
 !  This routine builds the base preconditioner corresponding to the current
-!  level of the multilevel preconditioner.
+!  level of the multilevel preconditioner. The routine first builds the
+!  (coarse) matrix associated to the current level from the (fine) matrix
+!  associated to the previous level, then builds the related base preconditioner.
 !
 ! 
 ! Arguments: