Esope source files

   1 : C DPERM     SOURCE    CHAT      05/01/12    22:54:41     5004           
   2 :       SUBROUTINE DPERM (NROW,A,JA,IA,AO,JAO,IAO,PERM,QPERM,JOB)
   3 :       IMPLICIT INTEGER(I-N)
   4 :       IMPLICIT REAL*8 (A-H,O-Z)
   5 : C***********************************************************************
   6 : C NOM         : DPERM
   7 : C DESCRIPTION : Permutation (lignes et colonnes) d'une matrice Morse. 
   8 : C
   9 : C
  10 : C LANGAGE     : FORTRAN 77
  11 : C ADAPTATION  :  Stéphane GOUNAND (CEA/DRN/DMT/SEMT/LTMF)
  12 : C                mél : gounand@semt2.smts.cea.fr
  13 : C AUTEUR      :
  14 : C  Sparskit : a basic tool kit for sparse matrix computations
  15 : C  Version 2 (Youcef Saad)
  16 : C  -> URL : http://www.cs.umn.edu/Research/arpa/SPARSKIT/sparskit.html
  17 : C
  18 : C***********************************************************************
  19 :       INTEGER NROW,JA(*),IA(NROW+1),JAO(*),IAO(NROW+1),PERM(NROW),
  20 :      +        QPERM(*),JOB
  21 :       REAL*8 A(*),AO(*) 
  22 : c-----------------------------------------------------------------------
  23 : c This routine permutes the rows and columns of a matrix stored in CSR
  24 : c format. i.e., it computes P A Q, where P, Q are permutation matrices. 
  25 : c P maps row i into row perm(i) and Q maps column j into column qperm(j): 
  26 : c      a(i,j)    becomes   a(perm(i),qperm(j)) in new matrix
  27 : c In the particular case where Q is the transpose of P (symmetric 
  28 : c permutation of A) then qperm is not needed. 
  29 : c note that qperm should be of length ncol (number of columns) but this
  30 : c is not checked. 
  31 : c-----------------------------------------------------------------------
  32 : c Y. Saad, Sep. 21 1989 / recoded Jan. 28 1991. 
  33 : c-----------------------------------------------------------------------
  34 : c on entry: 
  35 : c---------- 
  36 : c n     = dimension of the matrix
  37 : c a, ja, 
  38 : c    ia = input matrix in a, ja, ia format
  39 : c perm  = integer array of length n containing the permutation arrays
  40 : c         for the rows: perm(i) is the destination of row i in the
  41 : c         permuted matrix -- also the destination of column i in case
  42 : c         permutation is symmetric (job .le. 2) 
  43 : c
  44 : c qperm = same thing for the columns. This should be provided only
  45 : c         if job=3 or job=4, i.e., only in the case of a nonsymmetric
  46 : c         permutation of rows and columns. Otherwise qperm is a dummy
  47 : c
  48 : c job   = integer indicating the work to be done:
  49 : c * job = 1,2 permutation is symmetric  Ao :== P * A * transp(P)
  50 : c               job = 1 permute a, ja, ia into ao, jao, iao 
  51 : c               job = 2 permute matrix ignoring real values.
  52 : c * job = 3,4 permutation is non-symmetric  Ao :== P * A * Q 
  53 : c               job = 3 permute a, ja, ia into ao, jao, iao 
  54 : c               job = 4 permute matrix ignoring real values.
  55 : c               
  56 : c on return: 
  57 : c-----------
  58 : c ao, jao, iao = input matrix in a, ja, ia format
  59 : c
  60 : c in case job .eq. 2 or job .eq. 4, a and ao are never referred to 
  61 : c and can be dummy arguments. 
  62 : c Notes:
  63 : c------- 
  64 : c  1) algorithm is in place (Faux ! vu que RPERM ne l'est pas)
  65 : c  2) column indices may not be sorted on return even  though they may be 
  66 : c     on entry.
  67 : c----------------------------------------------------------------------c
  68 : c local variables 
  69 :       INTEGER LOCJOB, MOD
  70 : c
  71 : c     locjob indicates whether or not real values must be copied. 
  72 : c     
  73 :       LOCJOB = MOD(JOB,2) 
  74 : c
  75 : c permute rows first 
  76 : c 
  76 :       CALL RPERM (NROW,A,JA,IA,AO,JAO,IAO,PERM,LOCJOB)
  77 : c
  78 : c then permute columns
  79 : c
  80 :       LOCJOB = 0
  81 : c
  82 :       IF (JOB .LE. 2) THEN
  82 :          CALL CPERM (NROW,AO,JAO,IAO,AO,JAO,IAO,PERM,LOCJOB) 
  83 :       ELSE 
  83 :          CALL CPERM (NROW,AO,JAO,IAO,AO,JAO,IAO,QPERM,LOCJOB) 
  84 :       ENDIF 
  85 : c     
  86 :       RETURN
  87 : c-------end-of-dperm----------------------------------------------------
  88 : c-----------------------------------------------------------------------
  89 :       END
  90 :  
  91 :