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SUBROUTINE STRSV( UPLO, TRANS, DIAG, N, A, LDA, X, INCX )
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* -- Automatically Tuned Linear Algebra Software (ATLAS)
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* (C) Copyright 2000 All Rights Reserved
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* -- ATLAS routine -- F77 Interface -- Version 3.2 -- December 15, 2000
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* -- Suggestions, comments, bugs reports should be sent to the follo-
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* wing e-mail address: atlas@cs.utk.edu
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* Author : Antoine P. Petitet
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* University of Tennessee - Innovative Computing Laboratory
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* Knoxville TN, 37996-1301, USA.
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* ---------------------------------------------------------------------
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* -- Copyright notice and Licensing terms:
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions, and the following disclaimer in
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* the documentation and/or other materials provided with the distri-
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* 3. The name of the University, the ATLAS group, or the names of its
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* contributors may not be used to endorse or promote products deri-
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* ved from this software without specific written permission.
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY
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* OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
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* CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
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* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
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* OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEO-
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* RY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (IN-
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* CLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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* ---------------------------------------------------------------------
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* .. Scalar Arguments ..
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CHARACTER*1 DIAG, TRANS, UPLO
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* .. Array Arguments ..
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REAL A( LDA, * ), X( * )
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* STRSV solves one of the systems of equations
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* A*x = b, or A'*x = b,
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* where b and x are n-element vectors and A is an n by n unit, or non-
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* unit, upper or lower triangular matrix.
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* No test for singularity or near-singularity is included in this
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* routine. Such tests must be performed before calling this routine.
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* UPLO (input) CHARACTER*1
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* On entry, UPLO specifies whether the matrix is an upper or
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* lower triangular matrix as follows:
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* UPLO = 'U' or 'u' A is an upper triangular matrix.
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* UPLO = 'L' or 'l' A is a lower triangular matrix.
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* TRANS (input) CHARACTER*1.
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* On entry, TRANS specifies the equations to be solved as fol-
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* TRANS = 'N' or 'n' A *x = b,
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* TRANS = 'T' or 't' A'*x = b,
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* TRANS = 'T' or 't' A'*x = b.
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* DIAG (input) CHARACTER*1
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* On entry, DIAG specifies whether or not A is unit triangu-
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* DIAG = 'U' or 'u' A is assumed to be unit triangular.
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* DIAG = 'N' or 'n' A is not assumed to be unit
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* On entry, N specifies the order of the matrix A. N must be at
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* least zero. Unchanged on exit.
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* A (input) REAL array
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* On entry, A is an array of dimension ( LDA, n ). Before entry
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* with UPLO = 'U' or 'u', the leading n by n upper triangular
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* part of the array A must contain the upper triangular matrix
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* and the strictly lower triangular part of A is not referen-
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* ced. Before entry with UPLO = 'L' or 'l', the leading n by n
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* lower triangular part of the array A must contain the lower
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* triangular matrix and the strictly upper triangular part of A
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* Note that when DIAG = 'U' or 'u', the diagonal elements of A
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* are not referenced either, but are assumed to be unity. Un-
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* LDA (input) INTEGER
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* On entry, LDA specifies the first dimension of A as declared
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* in the calling (sub) program. LDA must be at least max(1,n).
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* X (input/output) REAL array
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* On entry, X is an incremented array of dimension at least
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* ( 1 + ( n - 1 ) * abs( INCX ) ). Before entry, the incremen-
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* ted array X must contain the n element right-hand side vector
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* b. On exit, X is overwritten with the solution vector x.
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* INCX (input) INTEGER
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* On entry, INCX specifies the increment for the elements of X.
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* INCX must not be zero. Unchanged on exit.
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* For further information on the Level 1 BLAS specification, see:
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* ``A Proposal for Standard Linear Algebra Subprograms'' by R. Hanson,
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* F. Krogh and C. Lawson, ACM SIGNUM Newsl., 8(16), 1973,
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* ``Basic Linear Algebra Subprograms for Fortran Usage'' by C. Lawson,
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* R. Hanson, D. Kincaid and F. Krogh, ACM Transactions on Mathematical
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* Software, 5(3) pp 308-323, 1979.
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* For further information on the Level 2 BLAS specification, see:
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* ``An Extended Set of FORTRAN Basic Linear Algebra Subprograms'' by
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* J. Dongarra, J. Du Croz, S. Hammarling and R. Hanson, ACM Transac-
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* tions on Mathematical Software, 14(1) pp 1-17, 1988.
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* ``Algorithm 656: An extended Set of Basic Linear Algebra Subprograms:
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* Model Implementation and Test Programs'' by J. Dongarra, J. Du Croz,
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* S. Hammarling and R. Hanson, ACM Transactions on Mathematical Soft-
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* ware, 14(1) pp 18-32, 1988.
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* For further information on the Level 3 BLAS specification, see:
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* ``A Set of Level 3 Basic Linear Algebra Subprograms'' by J. Dongarra,
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* J. Du Croz, I. Duff and S. Hammarling, ACM Transactions on Mathemati-
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* cal Software, 16(1), pp 1-17, 1990.
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* =====================================================================
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INTEGER ILOWER, IUPPER
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PARAMETER ( IUPPER = 121, ILOWER = 122 )
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INTEGER ICOTRAN, INOTRAN, ITRAN
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PARAMETER ( INOTRAN = 111, ITRAN = 112, ICOTRAN = 113 )
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INTEGER INONUNIT, IUNIT
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PARAMETER ( INONUNIT = 131, IUNIT = 132 )
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* .. Local Scalars ..
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INTEGER IDIAG, INFO, ITRANS, IUPLO
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* .. External Subroutines ..
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EXTERNAL ATL_F77WRAP_STRSV, XERBLA
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* .. External Functions ..
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* .. Intrinsic Functions ..
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* .. Executable Statements ..
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IF( LSAME( UPLO , 'U' ) ) THEN
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ELSE IF( LSAME( UPLO , 'L' ) ) THEN
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ELSE IF( INFO.EQ.0 ) THEN
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IF( LSAME( TRANS, 'N' ) ) THEN
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ELSE IF( LSAME( TRANS, 'T' ) ) THEN
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ELSE IF( LSAME( TRANS, 'C' ) ) THEN
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ELSE IF( INFO.EQ.0 ) THEN
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IF( LSAME( DIAG , 'N' ) ) THEN
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ELSE IF( LSAME( DIAG , 'U' ) ) THEN
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ELSE IF( INFO.EQ.0 ) THEN
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ELSE IF( LDA.LT.MAX( 1, N ) ) THEN
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ELSE IF( INCX.EQ.0 ) THEN
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CALL XERBLA( 'STRSV ', INFO )
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CALL ATL_F77WRAP_STRSV( IUPLO, ITRANS, IDIAG, N, A, LDA,
added
removed
interfaces/blas/F77/src/strsv.f
