1SLAGTM(1)           LAPACK auxiliary routine (version 3.2)           SLAGTM(1)
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NAME

6       SLAGTM  - performs a matrix-vector product of the form   B := alpha * A
7       * X + beta * B  where A is a tridiagonal matrix of order N, B and X are
8       N  by NRHS matrices, and alpha and beta are real scalars, each of which
9       may be 0., 1., or -1
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SYNOPSIS

12       SUBROUTINE SLAGTM( TRANS, N, NRHS, ALPHA, DL, D, DU, X, LDX,  BETA,  B,
13                          LDB )
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15           CHARACTER      TRANS
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17           INTEGER        LDB, LDX, N, NRHS
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19           REAL           ALPHA, BETA
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21           REAL           B( LDB, * ), D( * ), DL( * ), DU( * ), X( LDX, * )
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PURPOSE

24       SLAGTM performs a matrix-vector product of the form
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ARGUMENTS

27       TRANS   (input) CHARACTER*1
28               Specifies  the operation applied to A.  = 'N':  No transpose, B
29               := alpha * A * X + beta * B
30               = 'T':  Transpose,    B := alpha * A'* X + beta * B
31               = 'C':  Conjugate transpose = Transpose
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33       N       (input) INTEGER
34               The order of the matrix A.  N >= 0.
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36       NRHS    (input) INTEGER
37               The number of right hand sides, i.e., the number of columns  of
38               the matrices X and B.
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40       ALPHA   (input) REAL
41               The  scalar alpha.  ALPHA must be 0., 1., or -1.; otherwise, it
42               is assumed to be 0.
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44       DL      (input) REAL array, dimension (N-1)
45               The (n-1) sub-diagonal elements of T.
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47       D       (input) REAL array, dimension (N)
48               The diagonal elements of T.
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50       DU      (input) REAL array, dimension (N-1)
51               The (n-1) super-diagonal elements of T.
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53       X       (input) REAL array, dimension (LDX,NRHS)
54               The N by NRHS matrix X.  LDX     (input)  INTEGER  The  leading
55               dimension of the array X.  LDX >= max(N,1).
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57       BETA    (input) REAL
58               The scalar beta.  BETA must be 0., 1., or -1.; otherwise, it is
59               assumed to be 1.
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61       B       (input/output) REAL array, dimension (LDB,NRHS)
62               On entry, the N by NRHS matrix B.  On exit, B is overwritten by
63               the matrix expression B := alpha * A * X + beta * B.
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65       LDB     (input) INTEGER
66               The leading dimension of the array B.  LDB >= max(N,1).
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70 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                       SLAGTM(1)
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