SLASET (3lapack)

initialize an m-by-n matrix A to BETA on the diagonal and ALPHA on the offdiagonals

SYNOPSIS

  SUBROUTINE SLASET( UPLO, M, N, ALPHA, BETA, A, LDA )

      CHARACTER      UPLO

      INTEGER        LDA, M, N

      REAL           ALPHA, BETA

      REAL           A( LDA, * )

PURPOSE

  SLASET initializes an m-by-n matrix A to BETA on the diagonal and ALPHA on
  the offdiagonals.

ARGUMENTS

  UPLO    (input) CHARACTER*1
          Specifies the part of the matrix A to be set.  = 'U':      Upper
          triangular part is set; the strictly lower triangular part of A is
          not changed.  = 'L':      Lower triangular part is set; the
          strictly upper triangular part of A is not changed.  Otherwise:
          All of the matrix A is set.

  M       (input) INTEGER
          The number of rows of the matrix A.  M >= 0.

  N       (input) INTEGER
          The number of columns of the matrix A.  N >= 0.

  ALPHA   (input) REAL
          The constant to which the offdiagonal elements are to be set.

  BETA    (input) REAL
          The constant to which the diagonal elements are to be set.

  A       (input/output) REAL array, dimension (LDA,N)
          On exit, the leading m-by-n submatrix of A is set as follows:

          if UPLO = 'U', A(i,j) = ALPHA, 1<=i<=j-1, 1<=j<=n, if UPLO = 'L',
          A(i,j) = ALPHA, j+1<=i<=m, 1<=j<=n, otherwise,     A(i,j) = ALPHA,
          1<=i<=m, 1<=j<=n, i.ne.j,

          and, for all UPLO, A(i,i) = BETA, 1<=i<=min(m,n).

  LDA     (input) INTEGER
          The leading dimension of the array A.  LDA >= max(1,M).