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

.in +1c
.ti -1c
.RI "subroutine \fBdstect\fP (n, a, b, shift, num)"
.br
.RI "\fBDSTECT\fP "
.in -1c
.SH "Function/Subroutine Documentation"
.PP 
.SS "subroutine dstect (integer n, double precision, dimension( * ) a, double precision, dimension( * ) b, double precision shift, integer num)"

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

.PP
.nf
    DSTECT counts the number NUM of eigenvalues of a tridiagonal
    matrix T which are less than or equal to SHIFT\&. T has
    diagonal entries A(1), \&.\&.\&. , A(N), and offdiagonal entries
    B(1), \&.\&.\&., B(N-1)\&.
    See W\&. Kahan 'Accurate Eigenvalues of a Symmetric Tridiagonal
    Matrix', Report CS41, Computer Science Dept\&., Stanford
    University, July 21, 1966
.fi
.PP
 
.RE
.PP
\fBParameters\fP
.RS 4
\fIN\fP 
.PP
.nf
          N is INTEGER
          The dimension of the tridiagonal matrix T\&.
.fi
.PP
.br
\fIA\fP 
.PP
.nf
          A is DOUBLE PRECISION array, dimension (N)
          The diagonal entries of the tridiagonal matrix T\&.
.fi
.PP
.br
\fIB\fP 
.PP
.nf
          B is DOUBLE PRECISION array, dimension (N-1)
          The offdiagonal entries of the tridiagonal matrix T\&.
.fi
.PP
.br
\fISHIFT\fP 
.PP
.nf
          SHIFT is DOUBLE PRECISION
          The shift, used as described under Purpose\&.
.fi
.PP
.br
\fINUM\fP 
.PP
.nf
          NUM is INTEGER
          The number of eigenvalues of T less than or equal
          to SHIFT\&.
.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 \fB81\fP of file \fBdstect\&.f\fP\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for LAPACK from the source code\&.