.TH "TESTING/LIN/strt02.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME TESTING/LIN/strt02.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBstrt02\fP (uplo, trans, diag, n, nrhs, a, lda, x, ldx, b, ldb, work, resid)" .br .RI "\fBSTRT02\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine strt02 (character uplo, character trans, character diag, integer n, integer nrhs, real, dimension( lda, * ) a, integer lda, real, dimension( ldx, * ) x, integer ldx, real, dimension( ldb, * ) b, integer ldb, real, dimension( * ) work, real resid)" .PP \fBSTRT02\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> STRT02 computes the residual for the computed solution to a !> triangular system of linear equations op(A)*X = B, where A is a !> triangular matrix\&. The test ratio is the maximum over !> norm(b - op(A)*x) / ( ||op(A)||_1 * norm(x) * EPS ), !> where op(A) = A or A**T, b is the column of B, x is the solution !> vector, and EPS is the machine epsilon\&. !> The norm used is the 1-norm\&. !> .fi .PP .RE .PP \fBParameters\fP .RS 4 \fIUPLO\fP .PP .nf !> UPLO is CHARACTER*1 !> Specifies whether the matrix A is upper or lower triangular\&. !> = 'U': Upper triangular !> = 'L': Lower triangular !> .fi .PP .br \fITRANS\fP .PP .nf !> TRANS is CHARACTER*1 !> Specifies the operation applied to A\&. !> = 'N': A * X = B (No transpose) !> = 'T': A**T * X = B (Transpose) !> = 'C': A**H * X = B (Conjugate transpose = Transpose) !> .fi .PP .br \fIDIAG\fP .PP .nf !> DIAG is CHARACTER*1 !> Specifies whether or not the matrix A is unit triangular\&. !> = 'N': Non-unit triangular !> = 'U': Unit triangular !> .fi .PP .br \fIN\fP .PP .nf !> N is INTEGER !> The order of the matrix A\&. N >= 0\&. !> .fi .PP .br \fINRHS\fP .PP .nf !> NRHS is INTEGER !> The number of right hand sides, i\&.e\&., the number of columns !> of the matrices X and B\&. NRHS >= 0\&. !> .fi .PP .br \fIA\fP .PP .nf !> A is REAL array, dimension (LDA,N) !> The triangular matrix A\&. If UPLO = 'U', the leading n by n !> upper triangular part of the array A contains the upper !> triangular matrix, and the strictly lower triangular part of !> A is not referenced\&. If UPLO = 'L', the leading n by n lower !> triangular part of the array A contains the lower triangular !> matrix, and the strictly upper triangular part of A is not !> referenced\&. If DIAG = 'U', the diagonal elements of A are !> also not referenced and are assumed to be 1\&. !> .fi .PP .br \fILDA\fP .PP .nf !> LDA is INTEGER !> The leading dimension of the array A\&. LDA >= max(1,N)\&. !> .fi .PP .br \fIX\fP .PP .nf !> X is REAL array, dimension (LDX,NRHS) !> The computed solution vectors for the system of linear !> equations\&. !> .fi .PP .br \fILDX\fP .PP .nf !> LDX is INTEGER !> The leading dimension of the array X\&. LDX >= max(1,N)\&. !> .fi .PP .br \fIB\fP .PP .nf !> B is REAL array, dimension (LDB,NRHS) !> The right hand side vectors for the system of linear !> equations\&. !> .fi .PP .br \fILDB\fP .PP .nf !> LDB is INTEGER !> The leading dimension of the array B\&. LDB >= max(1,N)\&. !> .fi .PP .br \fIWORK\fP .PP .nf !> WORK is REAL array, dimension (N) !> .fi .PP .br \fIRESID\fP .PP .nf !> RESID is REAL !> The maximum over the number of right hand sides of !> norm(op(A)*X - B) / ( norm(op(A)) * norm(X) * EPS )\&. !> .fi .PP .RE .PP \fBAuthor\fP .RS 4 Univ\&. of Tennessee .PP Univ\&. of California Berkeley .PP Univ\&. of Colorado Denver .PP NAG Ltd\&. .RE .PP .PP Definition at line \fB148\fP of file \fBstrt02\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.