.TH "TESTING/EIG/ssvdct.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME TESTING/EIG/ssvdct.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBssvdct\fP (n, s, e, shift, num)" .br .RI "\fBSSVDCT\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine ssvdct (integer n, real, dimension( * ) s, real, dimension( * ) e, real shift, integer num)" .PP \fBSSVDCT\fP .PP \fBPurpose:\fP .RS 4 .PP .nf !> !> SSVDCT counts the number NUM of eigenvalues of a 2*N by 2*N !> tridiagonal matrix T which are less than or equal to SHIFT\&. T is !> formed by putting zeros on the diagonal and making the off-diagonals !> equal to S(1), E(1), S(2), E(2), \&.\&.\&. , E(N-1), S(N)\&. If SHIFT is !> positive, NUM is equal to N plus the number of singular values of a !> bidiagonal matrix B less than or equal to SHIFT\&. Here B has diagonal !> entries S(1), \&.\&.\&., S(N) and superdiagonal entries E(1), \&.\&.\&. E(N-1)\&. !> If SHIFT is negative, NUM is equal to the number of singular values !> of B greater than or equal to -SHIFT\&. !> !> See W\&. Kahan , 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 bidiagonal matrix B\&. !> .fi .PP .br \fIS\fP .PP .nf !> S is REAL array, dimension (N) !> The diagonal entries of the bidiagonal matrix B\&. !> .fi .PP .br \fIE\fP .PP .nf !> E is REAL array of dimension (N-1) !> The superdiagonal entries of the bidiagonal matrix B\&. !> .fi .PP .br \fISHIFT\fP .PP .nf !> SHIFT is REAL !> 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 \fB86\fP of file \fBssvdct\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.