1ZSYR(1)             LAPACK auxiliary routine (version 3.1)             ZSYR(1)
2
3
4

NAME

6       ZSYR - the symmetric rank 1 operation   A := alpha*x*( x' ) + A,
7

SYNOPSIS

9       SUBROUTINE ZSYR( UPLO, N, ALPHA, X, INCX, A, LDA )
10
11           CHARACTER    UPLO
12
13           INTEGER      INCX, LDA, N
14
15           COMPLEX*16   ALPHA
16
17           COMPLEX*16   A( LDA, * ), X( * )
18

PURPOSE

20       ZSYR   performs the symmetric rank 1 operation
21
22       where alpha is a complex scalar, x is an n element vector and A is an n
23       by n symmetric matrix.
24
25

ARGUMENTS

27       UPLO     (input) CHARACTER*1
28                On entry, UPLO specifies whether the upper or lower triangular
29                part of the array A is to be referenced as follows:
30
31                UPLO  = 'U' or 'u'   Only the upper triangular part of A is to
32                be referenced.
33
34                UPLO = 'L' or 'l'   Only the lower triangular part of A is  to
35                be referenced.
36
37                Unchanged on exit.
38
39       N        (input) INTEGER
40                On entry, N specifies the order of the matrix A.  N must be at
41                least zero.  Unchanged on exit.
42
43       ALPHA    (input) COMPLEX*16
44                On entry, ALPHA specifies  the  scalar  alpha.   Unchanged  on
45                exit.
46
47       X        (input) COMPLEX*16 array, dimension at least
48                (  1 + ( N - 1 )*abs( INCX ) ).  Before entry, the incremented
49                array X must contain the N- element vector  x.   Unchanged  on
50                exit.
51
52       INCX     (input) INTEGER
53                On  entry, INCX specifies the increment for the elements of X.
54                INCX must not be zero.  Unchanged on exit.
55
56       A        (input/output) COMPLEX*16 array, dimension ( LDA, N )
57                Before entry, with  UPLO = 'U' or 'u',  the  leading  n  by  n
58                upper  triangular  part  of the array A must contain the upper
59                triangular part of the symmetric matrix and the strictly lower
60                triangular  part  of  A  is not referenced. On exit, the upper
61                triangular part of the array A is  overwritten  by  the  upper
62                triangular  part  of  the  updated matrix.  Before entry, with
63                UPLO = 'L' or 'l', the leading n by n lower triangular part of
64                the array A must contain the lower triangular part of the sym‐
65                metric matrix and the strictly upper triangular part of  A  is
66                not  referenced.  On  exit,  the  lower triangular part of the
67                array A is overwritten by the lower  triangular  part  of  the
68                updated matrix.
69
70       LDA      (input) INTEGER
71                On  entry,  LDA specifies the first dimension of A as declared
72                in the calling (sub) program. LDA must be at least max(  1,  N
73                ).  Unchanged on exit.
74
75
76
77 LAPACK auxiliary routine (versionNo3v.e1m)ber 2006                         ZSYR(1)
Impressum