LAPACK  3.4.0
LAPACK: Linear Algebra PACKage
Functions/Subroutines
zlagtm.f File Reference

Go to the source code of this file.

Functions/Subroutines

subroutine ZLAGTM (TRANS, N, NRHS, ALPHA, DL, D, DU, X, LDX, BETA, B, LDB)
 ZLAGTM

Function/Subroutine Documentation

subroutine ZLAGTM ( CHARACTER  TRANS,
INTEGER  N,
INTEGER  NRHS,
DOUBLE PRECISION  ALPHA,
COMPLEX*16, dimension( * )  DL,
COMPLEX*16, dimension( * )  D,
COMPLEX*16, dimension( * )  DU,
COMPLEX*16, dimension( ldx, * )  X,
INTEGER  LDX,
DOUBLE PRECISION  BETA,
COMPLEX*16, dimension( ldb, * )  B,
INTEGER  LDB 
)

ZLAGTM

Download ZLAGTM + dependencies [TGZ] [ZIP] [TXT]
Purpose: 

 ZLAGTM performs a matrix-vector product of the form

    B := alpha * A * X + beta * B

 where A is a tridiagonal matrix of order N, B and X are N by NRHS
 matrices, and alpha and beta are real scalars, each of which may be
 0., 1., or -1.
Parameters:
[in]TRANS
          TRANS is CHARACTER*1
          Specifies the operation applied to A.
          = 'N':  No transpose, B := alpha * A * X + beta * B
          = 'T':  Transpose,    B := alpha * A**T * X + beta * B
          = 'C':  Conjugate transpose, B := alpha * A**H * X + beta * B
[in]N
          N is INTEGER
          The order of the matrix A.  N >= 0.
[in]NRHS
          NRHS is INTEGER
          The number of right hand sides, i.e., the number of columns
          of the matrices X and B.
[in]ALPHA
          ALPHA is DOUBLE PRECISION
          The scalar alpha.  ALPHA must be 0., 1., or -1.; otherwise,
          it is assumed to be 0.
[in]DL
          DL is COMPLEX*16 array, dimension (N-1)
          The (n-1) sub-diagonal elements of T.
[in]D
          D is COMPLEX*16 array, dimension (N)
          The diagonal elements of T.
[in]DU
          DU is COMPLEX*16 array, dimension (N-1)
          The (n-1) super-diagonal elements of T.
[in]X
          X is COMPLEX*16 array, dimension (LDX,NRHS)
          The N by NRHS matrix X.
[in]LDX
          LDX is INTEGER
          The leading dimension of the array X.  LDX >= max(N,1).
[in]BETA
          BETA is DOUBLE PRECISION
          The scalar beta.  BETA must be 0., 1., or -1.; otherwise,
          it is assumed to be 1.
[in,out]B
          B is COMPLEX*16 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.
[in]LDB
          LDB is INTEGER
          The leading dimension of the array B.  LDB >= max(N,1).
Author:
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
Date:
November 2011

Definition at line 145 of file zlagtm.f.

Here is the caller graph for this function:

 All Files Functions