cgtts2 (3p)

Name

cgtts2 - solve a system of linear equations with a tridiagonal matrix using the LU factorization computed by cgttrf

Synopsis

SUBROUTINE CGTTS2(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


INTEGER ITRANS, LDB, N, NRHS

INTEGER IPIV(*)

COMPLEX B(LDB,*), D(*), DL(*), DU(*), DU2(*)


SUBROUTINE CGTTS2_64(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


INTEGER*8 ITRANS, LDB, N, NRHS

INTEGER*8 IPIV(*)

COMPLEX B(LDB,*), D(*), DL(*), DU(*), DU2(*)


F95 INTERFACE
SUBROUTINE GTTS2(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


INTEGER :: ITRANS, N, NRHS, LDB

INTEGER, DIMENSION(:) :: IPIV

COMPLEX, DIMENSION(:,:) :: B

COMPLEX, DIMENSION(:) :: DL, D, DU, DU2


SUBROUTINE GTTS2_64(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


INTEGER(8) :: ITRANS, N, NRHS, LDB

INTEGER(8), DIMENSION(:) :: IPIV

COMPLEX, DIMENSION(:,:) :: B

COMPLEX, DIMENSION(:) :: DL, D, DU, DU2


C INTERFACE
#include <sunperf.h>

void cgtts2 (int itrans, int n, int nrhs, floatcomplex  *dl,  floatcom-
plex  *d,  floatcomplex  *du,  floatcomplex  *du2, int *ipiv,
floatcomplex *b, int ldb);


void cgtts2_64 (long itrans,  long  n,  long  nrhs,  floatcomplex  *dl,
floatcomplex  *d,  floatcomplex  *du, floatcomplex *du2, long
*ipiv, floatcomplex *b, long ldb);

Description

Oracle Solaris Studio Performance Library                           cgtts2(3P)



NAME
       cgtts2  -  solve a system of linear equations with a tridiagonal matrix
       using the LU factorization computed by cgttrf


SYNOPSIS
       SUBROUTINE CGTTS2(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


       INTEGER ITRANS, LDB, N, NRHS

       INTEGER IPIV(*)

       COMPLEX B(LDB,*), D(*), DL(*), DU(*), DU2(*)


       SUBROUTINE CGTTS2_64(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


       INTEGER*8 ITRANS, LDB, N, NRHS

       INTEGER*8 IPIV(*)

       COMPLEX B(LDB,*), D(*), DL(*), DU(*), DU2(*)


   F95 INTERFACE
       SUBROUTINE GTTS2(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


       INTEGER :: ITRANS, N, NRHS, LDB

       INTEGER, DIMENSION(:) :: IPIV

       COMPLEX, DIMENSION(:,:) :: B

       COMPLEX, DIMENSION(:) :: DL, D, DU, DU2


       SUBROUTINE GTTS2_64(ITRANS, N, NRHS, DL, D, DU, DU2, IPIV, B, LDB)


       INTEGER(8) :: ITRANS, N, NRHS, LDB

       INTEGER(8), DIMENSION(:) :: IPIV

       COMPLEX, DIMENSION(:,:) :: B

       COMPLEX, DIMENSION(:) :: DL, D, DU, DU2


   C INTERFACE
       #include <sunperf.h>

       void cgtts2 (int itrans, int n, int nrhs, floatcomplex  *dl,  floatcom-
                 plex  *d,  floatcomplex  *du,  floatcomplex  *du2, int *ipiv,
                 floatcomplex *b, int ldb);


       void cgtts2_64 (long itrans,  long  n,  long  nrhs,  floatcomplex  *dl,
                 floatcomplex  *d,  floatcomplex  *du, floatcomplex *du2, long
                 *ipiv, floatcomplex *b, long ldb);


PURPOSE
       cgtts2 solves one of the systems of  equations  A*X=B,   A**T*X=B,   or
       A**H*X=B,  with  a tridiagonal matrix A using the LU factorization com-
       puted by CGTTRF.



ARGUMENTS
       ITRANS (input)
                 ITRANS is INTEGER
                 Specifies the form of the system of equations.
                 = 0:  A * X = B     (No transpose),
                 = 1:  A**T * X = B  (Transpose),
                 = 2:  A**H * X = B  (Conjugate transpose).


       N (input)
                 N is INTEGER
                 The order of the matrix A.


       NRHS (input)
                 NRHS is INTEGER
                 The number of right hand sides, i.e., the number  of  columns
                 of the matrix B. NRHS >= 0.


       DL (input)
                 DL is COMPLEX array, dimension (N-1)
                 The  (N-1)  multipliers  that define the matrix L from the LU
                 factorization of A.


       D (input)
                 D is COMPLEX array, dimension (N)
                 The n diagonal elements of the upper triangular matrix U from
                 the LU factorization of A.


       DU (input)
                 DU is COMPLEX array, dimension (N-1)
                 The (N-1) elements of the first super-diagonal of U.


       DU2 (input)
                 DU2 is COMPLEX array, dimension (N-2)
                 The (N-2) elements of the second super-diagonal of U.


       IPIV (input)
                 IPIV is INTEGER array, dimension (N)
                 The  pivot  indices; for 1 <= i <= N, row i of the matrix was
                 interchanged with row IPIV(i). IPIV(i) will always be  either
                 i  or  i+1;  IPIV(i)  = i indicates a row interchange was not
                 required.


       B (input/output)
                 B is COMPLEX array, dimension (LDB,NRHS)
                 On entry, the matrix of right hand side vectors B.
                 On exit, B is overwritten by the solution vectors X.


       LDB (input)
                 LDB is INTEGER
                 The leading dimension of the array B. LDB >= max(1,N).




                                  7 Nov 2015                        cgtts2(3P)