TESTING/LIN/zqrt17.f(3) Library Functions Manual TESTING/LIN/zqrt17.f(3) NAME TESTING/LIN/zqrt17.f SYNOPSIS Functions/Subroutines double precision function zqrt17 (trans, iresid, m, n, nrhs, a, lda, x, ldx, b, ldb, c, work, lwork) ZQRT17 Function/Subroutine Documentation double precision function zqrt17 (character trans, integer iresid, integer m, integer n, integer nrhs, complex*16, dimension( lda, * ) a, integer lda, complex*16, dimension( ldx, * ) x, integer ldx, complex*16, dimension( ldb, * ) b, integer ldb, complex*16, dimension( ldb, * ) c, complex*16, dimension( lwork ) work, integer lwork) ZQRT17 Purpose: !> !> ZQRT17 computes the ratio !> !> norm(R**H * op(A)) / ( norm(A) * alpha * max(M,N,NRHS) * EPS ), !> !> where R = B - op(A)*X, op(A) is A or A**H, depending on TRANS, EPS !> is the machine epsilon, and !> !> alpha = norm(B) if IRESID = 1 (zero-residual problem) !> alpha = norm(R) if IRESID = 2 (otherwise). !> !> The norm used is the 1-norm. !> Parameters TRANS !> TRANS is CHARACTER*1 !> Specifies whether or not the transpose of A is used. !> = 'N': No transpose, op(A) = A. !> = 'C': Conjugate transpose, op(A) = A**H. !> IRESID !> IRESID is INTEGER !> IRESID = 1 indicates zero-residual problem. !> IRESID = 2 indicates non-zero residual. !> M !> M is INTEGER !> The number of rows of the matrix A. !> If TRANS = 'N', the number of rows of the matrix B. !> If TRANS = 'C', the number of rows of the matrix X. !> N !> N is INTEGER !> The number of columns of the matrix A. !> If TRANS = 'N', the number of rows of the matrix X. !> If TRANS = 'C', the number of rows of the matrix B. !> NRHS !> NRHS is INTEGER !> The number of columns of the matrices X and B. !> A !> A is COMPLEX*16 array, dimension (LDA,N) !> The m-by-n matrix A. !> LDA !> LDA is INTEGER !> The leading dimension of the array A. LDA >= M. !> X !> X is COMPLEX*16 array, dimension (LDX,NRHS) !> If TRANS = 'N', the n-by-nrhs matrix X. !> If TRANS = 'C', the m-by-nrhs matrix X. !> LDX !> LDX is INTEGER !> The leading dimension of the array X. !> If TRANS = 'N', LDX >= N. !> If TRANS = 'C', LDX >= M. !> B !> B is COMPLEX*16 array, dimension (LDB,NRHS) !> If TRANS = 'N', the m-by-nrhs matrix B. !> If TRANS = 'C', the n-by-nrhs matrix B. !> LDB !> LDB is INTEGER !> The leading dimension of the array B. !> If TRANS = 'N', LDB >= M. !> If TRANS = 'C', LDB >= N. !> C !> C is COMPLEX*16 array, dimension (LDB,NRHS) !> WORK !> WORK is COMPLEX*16 array, dimension (LWORK) !> LWORK !> LWORK is INTEGER !> The length of the array WORK. LWORK >= NRHS*(M+N). !> Author Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Definition at line 151 of file zqrt17.f. Author Generated automatically by Doxygen for LAPACK from the source code. LAPACK Version 3.12.0 TESTING/LIN/zqrt17.f(3)