[ новости /+++ | форум | теги | ]

NAME
     slasy2 - solve for the N1 by N2 matrix X, 1 <= N1,N2  <=  2,
     in   op(TL)*X + ISGN*X*op(TR) = SCALE*B,

SYNOPSIS
     SUBROUTINE SLASY2( LTRANL, LTRANR, ISGN, N1, N2,  TL,  LDTL,
               TR, LDTR, B, LDB, SCALE, X, LDX, XNORM, INFO )

     LOGICAL LTRANL, LTRANR

     INTEGER INFO, ISGN, LDB, LDTL, LDTR, LDX, N1, N2

     REAL SCALE, XNORM

     REAL B( LDB, * ), TL( LDTL, * ), TR( LDTR, * ), X( LDX, * )



     #include <sunperf.h>

     void slasy2(int ltranl, int ltranr, int isgn,  int  n1,  int
               n2,  float  *tl,  int  ldtl,  float *tr, int ldtr,
               float *sb, int ldb, float *sscale, float *sx,  int
               ldx, float *xnorm, int *info) ;

PURPOSE
     SLASY2 solves for the N1 by N2 matrix X, 1 <= N1,N2 <= 2, in

     where TL is N1 by N1, TR is N2 by N2, B is  N1  by  N2,  and
     ISGN = 1 or -1.  op(T) = T or T', where T' denotes the tran-
     spose of T.


ARGUMENTS
     LTRANL    (input) LOGICAL
               On entry, LTRANL specifies the op(TL):  = .FALSE.,
               op(TL) = TL, = .TRUE., op(TL) = TL'.

     LTRANR    (input) LOGICAL
               On entry, LTRANR specifies the op(TR):  = .FALSE.,
               op(TR) = TR, = .TRUE., op(TR) = TR'.

     ISGN      (input) INTEGER
               On entry, ISGN specifies the sign of the  equation
               as described before. ISGN may only be 1 or -1.

     N1        (input) INTEGER
               On entry, N1 specifies the order of matrix TL.  N1
               may only be 0, 1 or 2.

     N2        (input) INTEGER
               On entry, N2 specifies the order of matrix TR.  N2
               may only be 0, 1 or 2.

     TL        (input) REAL array, dimension (LDTL,2)
               On entry, TL contains an N1 by N1 matrix.

     LDTL      (input) INTEGER
               The leading dimension of the matrix  TL.  LDTL  >=
               max(1,N1).

     TR        (input) REAL array, dimension (LDTR,2)
               On entry, TR contains an N2 by N2 matrix.

     LDTR      (input) INTEGER
               The leading dimension of the matrix  TR.  LDTR  >=
               max(1,N2).

     B         (input) REAL array, dimension (LDB,2)
               On entry, the N1  by  N2  matrix  B  contains  the
               right-hand side of the equation.

     LDB       (input) INTEGER
               The leading dimension of  the  matrix  B.  LDB  >=
               max(1,N1).

     SCALE     (output) REAL
               On exit, SCALE contains the scale factor. SCALE is
               chosen  less  than  or  equal  to 1 to prevent the
               solution overflowing.

     X         (output) REAL array, dimension (LDX,2)
               On exit, X contains the N1 by N2 solution.

     LDX       (input) INTEGER
               The leading dimension of  the  matrix  X.  LDX  >=
               max(1,N1).

     XNORM     (output) REAL
               On exit, XNORM is the infinity-norm of  the  solu-
               tion.

     INFO      (output) INTEGER
               On exit, INFO is set to 0: successful exit.
               1: TL and TR have too close eigenvalues, so TL  or
               TR  is  perturbed  to  get a nonsingular equation.
               NOTE: In the interests of speed, this routine does
               not check the inputs for errors.

Партнёры:

Хостинг: