dtrsv - solve one of the systems of equations A*x = b, or A'*x = b
SUBROUTINE DTRSV(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER N, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) SUBROUTINE DTRSV_64(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER*8 N, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) F95 INTERFACE SUBROUTINE TRSV(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER :: N, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A SUBROUTINE TRSV_64(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER(8) :: N, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dtrsv(char uplo, char transa, char diag, int n, double *a, int lda, double *y, int incy); void dtrsv_64(char uplo, char transa, char diag, long n, double *a, long lda, double *y, long incy);
Oracle Solaris Studio Performance Library dtrsv(3P) NAME dtrsv - solve one of the systems of equations A*x = b, or A'*x = b SYNOPSIS SUBROUTINE DTRSV(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER N, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) SUBROUTINE DTRSV_64(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER*1 UPLO, TRANSA, DIAG INTEGER*8 N, LDA, INCY DOUBLE PRECISION A(LDA,*), Y(*) F95 INTERFACE SUBROUTINE TRSV(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER :: N, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A SUBROUTINE TRSV_64(UPLO, TRANSA, DIAG, N, A, LDA, Y, INCY) CHARACTER(LEN=1) :: UPLO, TRANSA, DIAG INTEGER(8) :: N, LDA, INCY REAL(8), DIMENSION(:) :: Y REAL(8), DIMENSION(:,:) :: A C INTERFACE #include <sunperf.h> void dtrsv(char uplo, char transa, char diag, int n, double *a, int lda, double *y, int incy); void dtrsv_64(char uplo, char transa, char diag, long n, double *a, long lda, double *y, long incy); PURPOSE dtrsv solves one of the systems of equations A*x = b, or A'*x = b, where b and x are n element vectors and A is an n by n unit, or non- unit, upper or lower triangular matrix. No test for singularity or near-singularity is included in this rou- tine. Such tests must be performed before calling this routine. ARGUMENTS UPLO (input) On entry, UPLO specifies whether the matrix is an upper or lower triangular matrix as follows: UPLO = 'U' or 'u' A is an upper triangular matrix. UPLO = 'L' or 'l' A is a lower triangular matrix. Unchanged on exit. TRANSA (input) On entry, TRANSA specifies the equations to be solved as fol- lows: TRANSA = 'N' or 'n' A*x = b. TRANSA = 'T' or 't' A'*x = b. TRANSA = 'C' or 'c' A'*x = b. Unchanged on exit. DIAG (input) On entry, DIAG specifies whether or not A is unit triangular as follows: DIAG = 'U' or 'u' A is assumed to be unit triangular. DIAG = 'N' or 'n' A is not assumed to be unit triangular. Unchanged on exit. N (input) On entry, N specifies the order of the matrix A. N >= 0. Unchanged on exit. A (input) Before entry with UPLO = 'U' or 'u', the leading n by n upper triangular part of the array A must contain the upper triangular matrix and the strictly lower triangular part of A is not referenced. Before entry with UPLO = 'L' or 'l', the leading n by n lower triangular part of the array A must con- tain the lower triangular matrix and the strictly upper tri- angular part of A is not referenced. Note that when DIAG = 'U' or 'u', the diagonal elements of A are not referenced either, but are assumed to be unity. Unchanged on exit. LDA (input) On entry, LDA specifies the first dimension of A as declared in the calling (sub) program. LDA >= max( 1, n ). Unchanged on exit. Y (input/output) ( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the incremented array Y must contain the n element right-hand side vector b. On exit, Y is overwritten with the solution vector x. INCY (input) On entry, INCY specifies the increment for the elements of Y. INCY <> 0. Unchanged on exit. 7 Nov 2015 dtrsv(3P)