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zgeru


 NAME
      ZGERU - perform the rank 1 operation   A := alpha*x*y' + A,

 SYNOPSIS
      SUBROUTINE ZGERU ( M, N, ALPHA, X, INCX, Y, INCY, A, LDA )

          COMPLEX*16   ALPHA

          INTEGER      INCX, INCY, LDA, M, N

          COMPLEX*16   A( LDA, * ), X( * ), Y( * )

 PURPOSE
      ZGERU  performs the rank 1 operation

      where alpha is a scalar, x is an m element vector, y is an n
      element vector and A is an m by n matrix.

 PARAMETERS
      M      - INTEGER.
             On entry, M specifies the number of rows of the
             matrix A.  M must be at least zero.  Unchanged on
             exit.

      N      - INTEGER.
             On entry, N specifies the number of columns of the
             matrix A.  N must be at least zero.  Unchanged on
             exit.

      ALPHA  - COMPLEX*16      .
             On entry, ALPHA specifies the scalar alpha.
             Unchanged on exit.

      X      - COMPLEX*16       array of dimension at least
             ( 1 + ( m - 1 )*abs( INCX ) ).  Before entry, the
             incremented array X must contain the m element vector
             x.  Unchanged on exit.

      INCX   - INTEGER.
             On entry, INCX specifies the increment for the ele-
             ments of X. INCX must not be zero.  Unchanged on
             exit.

      Y      - COMPLEX*16       array of dimension at least
             ( 1 + ( n - 1 )*abs( INCY ) ).  Before entry, the
             incremented array Y must contain the n element vector
             y.  Unchanged on exit.

      INCY   - INTEGER.
             On entry, INCY specifies the increment for the ele-
             ments of Y. INCY must not be zero.  Unchanged on

             exit.

      A      - COMPLEX*16       array of DIMENSION ( LDA, n ).
             Before entry, the leading m by n part of the array A
             must contain the matrix of coefficients. On exit, A
             is overwritten by the updated matrix.

      LDA    - INTEGER.
             On entry, LDA specifies the first dimension of A as
             declared in the calling (sub) program. LDA must be at
             least max( 1, m ).  Unchanged on exit.

             Level 2 Blas routine.

             -- Written on 22-October-1986.  Jack Dongarra,
             Argonne National Lab.  Jeremy Du Croz, Nag Central
             Office.  Sven Hammarling, Nag Central Office.
             Richard Hanson, Sandia National Labs.