.TH PZPTTRS l "12 May 1997" "LAPACK version 1.5" "LAPACK routine (version 1.5)" .SH NAME PZPTTRS \- solve a system of linear equations A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS) .SH SYNOPSIS .TP 20 SUBROUTINE PZPTTRS( UPLO, N, NRHS, D, E, JA, DESCA, B, IB, DESCB, AF, LAF, WORK, LWORK, INFO ) .TP 20 .ti +4 CHARACTER UPLO .TP 20 .ti +4 INTEGER IB, INFO, JA, LAF, LWORK, N, NRHS .TP 20 .ti +4 INTEGER DESCA( * ), DESCB( * ) .TP 20 .ti +4 COMPLEX*16 AF( * ), B( * ), E( * ), WORK( * ) .TP 20 .ti +4 DOUBLE PRECISION D( * ) .SH PURPOSE PZPTTRS solves a system of linear equations where A(1:N, JA:JA+N-1) is the matrix used to produce the factors stored in A(1:N,JA:JA+N-1) and AF by PZPTTRF. .br A(1:N, JA:JA+N-1) is an N-by-N complex .br tridiagonal symmetric positive definite distributed .br matrix. .br Depending on the value of UPLO, A stores either U or L in the equn A(1:N, JA:JA+N-1) = U'D *U or L*D L' as computed by PZPTTRF. Routine PZPTTRF MUST be called first. .br