The OpenNET Project / Index page

[ новости /+++ | форум | теги | ]

Интерактивная система просмотра системных руководств (man-ов)

 ТемаНаборКатегория 
 
 [Cписок руководств | Печать]

sporfs (3)
  • >> sporfs (3) ( Solaris man: Библиотечные вызовы )
  • 
    NAME
         sporfs - improve the computed solution to a system of linear
         equations  when the coefficient matrix is symmetric positive
         definite,
    
    SYNOPSIS
         SUBROUTINE SPORFS( UPLO, N, NRHS, A, LDA, AF, LDAF, B,  LDB,
                   X, LDX, FERR, BERR, WORK, IWORK, INFO )
    
         CHARACTER UPLO
    
         INTEGER INFO, LDA, LDAF, LDB, LDX, N, NRHS
    
         INTEGER IWORK( * )
    
         REAL A( LDA, * ), AF( LDAF, * ), B( LDB, *  ),  BERR(  *  ),
                   FERR( * ), WORK( * ), X( LDX, * )
    
    
    
         #include <sunperf.h>
    
         void sporfs(char uplo, int n, int nrhs, float *sa, int  lda,
                   float  *af,  int  ldaf,  float *sb, int ldb, float
                   *sx,  int  ldx,  float  *ferr,  float  *berr,  int
                   *info);
    
    PURPOSE
         SPORFS improves the computed solution to a system of  linear
         equations  when the coefficient matrix is symmetric positive
         definite, and provides error bounds and backward error esti-
         mates for the solution.
    
    
    ARGUMENTS
         UPLO      (input) CHARACTER*1
                   = 'U':  Upper triangle of A is stored;
                   = 'L':  Lower triangle of A is stored.
    
         N         (input) INTEGER
                   The order of the matrix A.  N >= 0.
    
         NRHS      (input) INTEGER
                   The number of right hand sides, i.e.,  the  number
                   of columns of the matrices B and X.  NRHS >= 0.
    
         A         (input) REAL array, dimension (LDA,N)
                   The symmetric matrix A.  If UPLO = 'U', the  lead-
                   ing N-by-N upper triangular part of A contains the
                   upper triangular part of the  matrix  A,  and  the
                   strictly  lower triangular part of A is not refer-
                   enced.  If UPLO = 'L', the  leading  N-by-N  lower
                   triangular part of A contains the lower triangular
                   part of the matrix A, and the strictly upper  tri-
                   angular part of A is not referenced.
    
         LDA       (input) INTEGER
                   The leading dimension of  the  array  A.   LDA  >=
                   max(1,N).
    
         AF        (input) REAL array, dimension (LDAF,N)
                   The triangular factor U or  L  from  the  Cholesky
                   factorization  A  =  U**T*U or A = L*L**T, as com-
                   puted by SPOTRF.
    
         LDAF      (input) INTEGER
                   The leading dimension of the array  AF.   LDAF  >=
                   max(1,N).
    
         B         (input) REAL array, dimension (LDB,NRHS)
                   The right hand side matrix B.
    
         LDB       (input) INTEGER
                   The leading dimension of  the  array  B.   LDB  >=
                   max(1,N).
    
         X         (input/output) REAL array, dimension (LDX,NRHS)
                   On entry, the solution matrix X,  as  computed  by
                   SPOTRS.  On exit, the improved solution matrix X.
    
         LDX       (input) INTEGER
                   The leading dimension of  the  array  X.   LDX  >=
                   max(1,N).
    
         FERR      (output) REAL array, dimension (NRHS)
                   The estimated forward error bound for  each  solu-
                   tion  vector X(j) (the j-th column of the solution
                   matrix  X).   If  XTRUE  is  the   true   solution
                   corresponding  to  X(j),  FERR(j)  is an estimated
                   upper bound for the magnitude of the largest  ele-
                   ment in (X(j) - XTRUE) divided by the magnitude of
                   the largest element in X(j).  The estimate  is  as
                   reliable  as the estimate for RCOND, and is almost
                   always a slight overestimate of the true error.
    
         BERR      (output) REAL array, dimension (NRHS)
                   The componentwise relative backward error of  each
                   solution  vector X(j) (i.e., the smallest relative
                   change in any element of A or B that makes X(j) an
                   exact solution).
    
         WORK      (workspace) REAL array, dimension (3*N)
    
         IWORK     (workspace) INTEGER array, dimension (N)
         INFO      (output) INTEGER
                   = 0:  successful exit
                   < 0:  if INFO = -i, the i-th argument had an ille-
                   gal value
    
    
    
    


    Поиск по тексту MAN-ов: 




    Партнёры:
    PostgresPro
    Inferno Solutions
    Hosting by Hoster.ru
    Хостинг:

    Закладки на сайте
    Проследить за страницей
    Created 1996-2024 by Maxim Chirkov
    Добавить, Поддержать, Вебмастеру