1DGER(1)                          BLAS routine                          DGER(1)
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NAME

6       DGER - performs the rank 1 operation   A := alpha*x*y' + A,
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SYNOPSIS

9       SUBROUTINE DGER(M,N,ALPHA,X,INCX,Y,INCY,A,LDA)
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11           DOUBLE                                     PRECISION ALPHA
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13           INTEGER                                    INCX,INCY,LDA,M,N
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15           DOUBLE                                     PRECISION
16                                                      A(LDA,*),X(*),Y(*)
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PURPOSE

19       DGER   performs the rank 1 operation
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21       where alpha is a scalar, x is an m element vector, y is  an  n  element
22       vector and A is an m by n matrix.
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ARGUMENTS

26       M      - INTEGER.
27              On  entry,  M  specifies  the number of rows of the matrix A.  M
28              must be at least zero.  Unchanged on exit.
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30       N      - INTEGER.
31              On entry, N specifies the number of columns of the matrix A.   N
32              must be at least zero.  Unchanged on exit.
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34       ALPHA  - DOUBLE PRECISION.
35              On entry, ALPHA specifies the scalar alpha.  Unchanged on exit.
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37       X      - DOUBLE PRECISION array of dimension at least
38              (  1  +  ( m - 1 )*abs( INCX ) ).  Before entry, the incremented
39              array X must contain the m element vector x.  Unchanged on exit.
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41       INCX   - INTEGER.
42              On entry, INCX specifies the increment for the  elements  of  X.
43              INCX must not be zero.  Unchanged on exit.
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45       Y      - DOUBLE PRECISION array of dimension at least
46              (  1  +  ( n - 1 )*abs( INCY ) ).  Before entry, the incremented
47              array Y must contain the n element vector y.  Unchanged on exit.
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49       INCY   - INTEGER.
50              On entry, INCY specifies the increment for the  elements  of  Y.
51              INCY must not be zero.  Unchanged on exit.
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53       A      - DOUBLE PRECISION array of DIMENSION ( LDA, n ).
54              Before  entry,  the leading m by n part of the array A must con‐
55              tain the matrix of coefficients. On exit, A  is  overwritten  by
56              the updated matrix.
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58       LDA    - INTEGER.
59              On  entry, LDA specifies the first dimension of A as declared in
60              the calling (sub) program. LDA must be at least  max(  1,  m  ).
61              Unchanged on exit.
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FURTHER DETAILS

64       Level 2 Blas routine.
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66       -- Written on 22-October-1986.
67          Jack Dongarra, Argonne National Lab.
68          Jeremy Du Croz, Nag Central Office.
69          Sven Hammarling, Nag Central Office.
70          Richard Hanson, Sandia National Labs.
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75BLAS routine                     November 2008                         DGER(1)