PCPTTRS(3) ScaLAPACK routine of NEC Numeric Library Collection PCPTTRS(3) NAME PCPTTRS - solve a system of linear equations A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS) SYNOPSIS SUBROUTINE PCPTTRS( UPLO, N, NRHS, D, E, JA, DESCA, B, IB, DESCB, AF, LAF, WORK, LWORK, INFO ) CHARACTER UPLO INTEGER IB, INFO, JA, LAF, LWORK, N, NRHS INTEGER DESCA( * ), DESCB( * ) COMPLEX AF( * ), B( * ), E( * ), WORK( * ) REAL D( * ) PURPOSE PCPTTRS solves a system of linear equations A(1:N, JA:JA+N-1) * X = B(IB:IB+N-1, 1:NRHS) where A(1:N, JA:JA+N-1) is the matrix used to pro- duce the factors stored in A(1:N,JA:JA+N-1) and AF by PCPTTRF. A(1:N, JA:JA+N-1) is an N-by-N complex tridiagonal symmetric positive definite distributed matrix. 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 PCPTTRF. Routine PCPTTRF MUST be called first. ScaLAPACK routine 31 October 2017 PCPTTRS(3)