.TH "TESTING/LIN/dlaptm.f" 3 "Version 3.12.0" "LAPACK" \" -*- nroff -*- .ad l .nh .SH NAME TESTING/LIN/dlaptm.f .SH SYNOPSIS .br .PP .SS "Functions/Subroutines" .in +1c .ti -1c .RI "subroutine \fBdlaptm\fP (n, nrhs, alpha, d, e, x, ldx, beta, b, ldb)" .br .RI "\fBDLAPTM\fP " .in -1c .SH "Function/Subroutine Documentation" .PP .SS "subroutine dlaptm (integer n, integer nrhs, double precision alpha, double precision, dimension( * ) d, double precision, dimension( * ) e, double precision, dimension( ldx, * ) x, integer ldx, double precision beta, double precision, dimension( ldb, * ) b, integer ldb)" .PP \fBDLAPTM\fP .PP \fBPurpose:\fP .RS 4 .PP .nf DLAPTM multiplies an N by NRHS matrix X by a symmetric tridiagonal matrix A and stores the result in a matrix B\&. The operation has the form B := alpha * A * X + beta * B where alpha may be either 1\&. or -1\&. and beta may be 0\&., 1\&., or -1\&. .fi .PP .RE .PP \fBParameters\fP .RS 4 \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\&. .fi .PP .br \fIALPHA\fP .PP .nf ALPHA is DOUBLE PRECISION The scalar alpha\&. ALPHA must be 1\&. or -1\&.; otherwise, it is assumed to be 0\&. .fi .PP .br \fID\fP .PP .nf D is DOUBLE PRECISION array, dimension (N) The n diagonal elements of the tridiagonal matrix A\&. .fi .PP .br \fIE\fP .PP .nf E is DOUBLE PRECISION array, dimension (N-1) The (n-1) subdiagonal or superdiagonal elements of A\&. .fi .PP .br \fIX\fP .PP .nf X is DOUBLE PRECISION array, dimension (LDX,NRHS) The N by NRHS matrix X\&. .fi .PP .br \fILDX\fP .PP .nf LDX is INTEGER The leading dimension of the array X\&. LDX >= max(N,1)\&. .fi .PP .br \fIBETA\fP .PP .nf BETA is DOUBLE PRECISION The scalar beta\&. BETA must be 0\&., 1\&., or -1\&.; otherwise, it is assumed to be 1\&. .fi .PP .br \fIB\fP .PP .nf B is DOUBLE PRECISION array, dimension (LDB,NRHS) On entry, the N by NRHS matrix B\&. On exit, B is overwritten by the matrix expression B := alpha * A * X + beta * B\&. .fi .PP .br \fILDB\fP .PP .nf LDB is INTEGER The leading dimension of the array B\&. LDB >= max(N,1)\&. .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 \fB115\fP of file \fBdlaptm\&.f\fP\&. .SH "Author" .PP Generated automatically by Doxygen for LAPACK from the source code\&.