1SLAGTM(1)           LAPACK auxiliary routine (version 3.1)           SLAGTM(1)
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NAME

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

28       TRANS   (input) CHARACTER*1
29               Specifies  the operation applied to A.  = 'N':  No transpose, B
30               := alpha * A * X + beta * B
31               = 'T':  Transpose,    B := alpha * A'* X + beta * B
32               = 'C':  Conjugate transpose = Transpose
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34       N       (input) INTEGER
35               The order of the matrix A.  N >= 0.
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37       NRHS    (input) INTEGER
38               The number of right hand sides, i.e., the number of columns  of
39               the matrices X and B.
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41       ALPHA   (input) REAL
42               The  scalar alpha.  ALPHA must be 0., 1., or -1.; otherwise, it
43               is assumed to be 0.
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45       DL      (input) REAL array, dimension (N-1)
46               The (n-1) sub-diagonal elements of T.
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48       D       (input) REAL array, dimension (N)
49               The diagonal elements of T.
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51       DU      (input) REAL array, dimension (N-1)
52               The (n-1) super-diagonal elements of T.
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54       X       (input) REAL array, dimension (LDX,NRHS)
55               The N by NRHS matrix X.  LDX     (input)  INTEGER  The  leading
56               dimension of the array X.  LDX >= max(N,1).
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58       BETA    (input) REAL
59               The scalar beta.  BETA must be 0., 1., or -1.; otherwise, it is
60               assumed to be 1.
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62       B       (input/output) REAL array, dimension (LDB,NRHS)
63               On entry, the N by NRHS matrix B.  On exit, B is overwritten by
64               the matrix expression B := alpha * A * X + beta * B.
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66       LDB     (input) INTEGER
67               The leading dimension of the array B.  LDB >= max(N,1).
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71 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                       SLAGTM(1)
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