.TH "TESTING/LIN/sqrt17.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
TESTING/LIN/sqrt17.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "real function \fBsqrt17\fP (trans, iresid, m, n, nrhs, a, lda, x, ldx, b, ldb, c, work, lwork)"
.br
.RI "\fBSQRT17\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "real function sqrt17 (character trans, integer iresid, integer m, integer n, integer nrhs, real, dimension( lda, * ) a, integer lda, real, dimension( ldx, * ) x, integer ldx, real, dimension( ldb, * ) b, integer ldb, real, dimension( ldb, * ) c, real, dimension( lwork ) work, integer lwork)"

.PP
\fBSQRT17\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
 SQRT17 computes the ratio

    norm(R**T * op(A)) / ( norm(A) * alpha * max(M,N,NRHS) * EPS ),

 where R = B - op(A)*X, op(A) is A or A**T, 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\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fITRANS\fP 
.PP
.nf
          TRANS is CHARACTER*1
          Specifies whether or not the transpose of A is used\&.
          = 'N':  No transpose, op(A) = A\&.
          = 'T':  Transpose, op(A) = A**T\&.
.fi
.PP
.br
\fIIRESID\fP 
.PP
.nf
          IRESID is INTEGER
          IRESID = 1 indicates zero-residual problem\&.
          IRESID = 2 indicates non-zero residual\&.
.fi
.PP
.br
\fIM\fP 
.PP
.nf
          M is INTEGER
          The number of rows of the matrix A\&.
          If TRANS = 'N', the number of rows of the matrix B\&.
          If TRANS = 'T', the number of rows of the matrix X\&.
.fi
.PP
.br
\fIN\fP 
.PP
.nf
          N is INTEGER
          The number of columns of the matrix  A\&.
          If TRANS = 'N', the number of rows of the matrix X\&.
          If TRANS = 'T', the number of rows of the matrix B\&.
.fi
.PP
.br
\fINRHS\fP 
.PP
.nf
          NRHS is INTEGER
          The number of columns of the matrices X and B\&.
.fi
.PP
.br
\fIA\fP 
.PP
.nf
          A is REAL array, dimension (LDA,N)
          The m-by-n matrix A\&.
.fi
.PP
.br
\fILDA\fP 
.PP
.nf
          LDA is INTEGER
          The leading dimension of the array A\&. LDA >= M\&.
.fi
.PP
.br
\fIX\fP 
.PP
.nf
          X is REAL array, dimension (LDX,NRHS)
          If TRANS = 'N', the n-by-nrhs matrix X\&.
          If TRANS = 'T', the m-by-nrhs matrix X\&.
.fi
.PP
.br
\fILDX\fP 
.PP
.nf
          LDX is INTEGER
          The leading dimension of the array X\&.
          If TRANS = 'N', LDX >= N\&.
          If TRANS = 'T', LDX >= M\&.
.fi
.PP
.br
\fIB\fP 
.PP
.nf
          B is REAL array, dimension (LDB,NRHS)
          If TRANS = 'N', the m-by-nrhs matrix B\&.
          If TRANS = 'T', the n-by-nrhs matrix B\&.
.fi
.PP
.br
\fILDB\fP 
.PP
.nf
          LDB is INTEGER
          The leading dimension of the array B\&.
          If TRANS = 'N', LDB >= M\&.
          If TRANS = 'T', LDB >= N\&.
.fi
.PP
.br
\fIC\fP 
.PP
.nf
          C is REAL array, dimension (LDB,NRHS)
.fi
.PP
.br
\fIWORK\fP 
.PP
.nf
          WORK is REAL array, dimension (LWORK)
.fi
.PP
.br
\fILWORK\fP 
.PP
.nf
          LWORK is INTEGER
          The length of the array WORK\&.  LWORK >= NRHS*(M+N)\&.
.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 \fB151\fP of file \fBsqrt17\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.