.TH "TESTING/LIN/stbt06.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*-
.ad l
.nh
.SH NAME
TESTING/LIN/stbt06.f
.SH SYNOPSIS
.br
.PP
.SS "Functions/Subroutines"

.in +1c
.ti -1c
.RI "subroutine \fBstbt06\fP (rcond, rcondc, uplo, diag, n, kd, ab, ldab, work, rat)"
.br
.RI "\fBSTBT06\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine stbt06 (real rcond, real rcondc, character uplo, character diag, integer n, integer kd, real, dimension( ldab, * ) ab, integer ldab, real, dimension( * ) work, real rat)"

.PP
\fBSTBT06\fP 
.PP
\fBPurpose:\fP
.RS 4

.PP
.nf
 STBT06 computes a test ratio comparing RCOND (the reciprocal
 condition number of a triangular matrix A) and RCONDC, the estimate
 computed by STBCON\&.  Information about the triangular matrix A is
 used if one estimate is zero and the other is non-zero to decide if
 underflow in the estimate is justified\&.
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIRCOND\fP 
.PP
.nf
          RCOND is REAL
          The estimate of the reciprocal condition number obtained by
          forming the explicit inverse of the matrix A and computing
          RCOND = 1/( norm(A) * norm(inv(A)) )\&.
.fi
.PP
.br
\fIRCONDC\fP 
.PP
.nf
          RCONDC is REAL
          The estimate of the reciprocal condition number computed by
          STBCON\&.
.fi
.PP
.br
\fIUPLO\fP 
.PP
.nf
          UPLO is CHARACTER
          Specifies whether the matrix A is upper or lower triangular\&.
          = 'U':  Upper triangular
          = 'L':  Lower triangular
.fi
.PP
.br
\fIDIAG\fP 
.PP
.nf
          DIAG is CHARACTER
          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
\fIKD\fP 
.PP
.nf
          KD is INTEGER
          The number of superdiagonals or subdiagonals of the
          triangular band matrix A\&.  KD >= 0\&.
.fi
.PP
.br
\fIAB\fP 
.PP
.nf
          AB is REAL array, dimension (LDAB,N)
          The upper or lower triangular band matrix A, stored in the
          first kd+1 rows of the array\&. The j-th column of A is stored
          in the j-th column of the array AB as follows:
          if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j;
          if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=min(n,j+kd)\&.
.fi
.PP
.br
\fILDAB\fP 
.PP
.nf
          LDAB is INTEGER
          The leading dimension of the array AB\&.  LDAB >= KD+1\&.
.fi
.PP
.br
\fIWORK\fP 
.PP
.nf
          WORK is REAL array, dimension (N)
.fi
.PP
.br
\fIRAT\fP 
.PP
.nf
          RAT is REAL
          The test ratio\&.  If both RCOND and RCONDC are nonzero,
             RAT = MAX( RCOND, RCONDC )/MIN( RCOND, RCONDC ) - 1\&.
          If RAT = 0, the two estimates are exactly the same\&.
.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 \fB123\fP of file \fBstbt06\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.