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

6       ZSYMV - performs the matrix-vector operation   y := alpha*A*x + beta*y,
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SYNOPSIS

9       SUBROUTINE ZSYMV( UPLO, N, ALPHA, A, LDA, X, INCX, BETA, Y, INCY )
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11           CHARACTER     UPLO
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13           INTEGER       INCX, INCY, LDA, N
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15           COMPLEX*16    ALPHA, BETA
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17           COMPLEX*16    A( LDA, * ), X( * ), Y( * )
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PURPOSE

20       ZSYMV   performs  the matrix-vector  operation where alpha and beta are
21       scalars, x and y are n element vectors and A is an  n  by  n  symmetric
22       matrix.
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ARGUMENTS

25       UPLO     (input) CHARACTER*1
26                On entry, UPLO specifies whether the upper or lower triangular
27                part of the array A is to be referenced as follows: UPLO = 'U'
28                or  'u'    Only the upper triangular part of A is to be refer‐
29                enced.  UPLO = 'L' or 'l'   Only the lower triangular part  of
30                A is to be referenced.  Unchanged on exit.
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32       N        (input) INTEGER
33                On entry, N specifies the order of the matrix A.  N must be at
34                least zero.  Unchanged on exit.
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36       ALPHA    (input) COMPLEX*16
37                On entry, ALPHA specifies  the  scalar  alpha.   Unchanged  on
38                exit.
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40       A        (input) COMPLEX*16 array, dimension ( LDA, N )
41                Before  entry,  with   UPLO  =  'U' or 'u', the leading n by n
42                upper triangular part of the array A must  contain  the  upper
43                triangular part of the symmetric matrix and the strictly lower
44                triangular part of A is not referenced.   Before  entry,  with
45                UPLO = 'L' or 'l', the leading n by n lower triangular part of
46                the array A must contain the lower triangular part of the sym‐
47                metric  matrix  and the strictly upper triangular part of A is
48                not referenced.  Unchanged on exit.
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50       LDA      (input) INTEGER
51                On entry, LDA specifies the first dimension of A  as  declared
52                in  the  calling (sub) program. LDA must be at least max( 1, N
53                ).  Unchanged on exit.
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55       X        (input) COMPLEX*16 array, dimension at least
56                ( 1 + ( N - 1 )*abs( INCX ) ).  Before entry, the  incremented
57                array  X  must  contain the N- element vector x.  Unchanged on
58                exit.
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60       INCX     (input) INTEGER
61                On entry, INCX specifies the increment for the elements of  X.
62                INCX must not be zero.  Unchanged on exit.
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64       BETA     (input) COMPLEX*16
65                On  entry,  BETA  specifies the scalar beta. When BETA is sup‐
66                plied as zero then Y need not be set on input.   Unchanged  on
67                exit.
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69       Y        (input/output) COMPLEX*16 array, dimension at least
70                (  1 + ( N - 1 )*abs( INCY ) ).  Before entry, the incremented
71                array Y must contain the n element vector y.  On  exit,  Y  is
72                overwritten by the updated vector y.
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74       INCY     (input) INTEGER
75                On  entry, INCY specifies the increment for the elements of Y.
76                INCY must not be zero.  Unchanged on exit.
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80 LAPACK auxiliary routine (versionNo3v.e2m)ber 2008                        ZSYMV(1)