ilazlc()

integer function ilazlc	(	integer	M,
		integer	N,
		complex*16, dimension( lda, * )	A,
		integer	LDA
	)

ILAZLC scans a matrix for its last non-zero column.

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Purpose:

 ILAZLC scans A for its last non-zero column.

Parameters

[in]	M	M is INTEGER The number of rows of the matrix A.
[in]	N	N is INTEGER The number of columns of the matrix A.
[in]	A	A is COMPLEX*16 array, dimension (LDA,N) The m by n matrix A.
[in]	LDA	LDA is INTEGER The leading dimension of the array A. LDA >= max(1,M).

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date

December 2016

Definition at line 80 of file ilazlc.f.

*
*  -- LAPACK auxiliary routine (version 3.7.0) --
*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
*     December 2016
*
*     .. Scalar Arguments ..
      INTEGER            M, N, LDA
*     ..
*     .. Array Arguments ..
      COMPLEX*16         A( LDA, * )
*     ..
*
*  =====================================================================
*
*     .. Parameters ..
      COMPLEX*16       ZERO
      parameter( zero = (0.0d+0, 0.0d+0) )
*     ..
*     .. Local Scalars ..
      INTEGER I
*     ..
*     .. Executable Statements ..
*
*     Quick test for the common case where one corner is non-zero.
      IF( n.EQ.0 ) THEN
         ilazlc = n
      ELSE IF( a(1, n).NE.zero .OR. a(m, n).NE.zero ) THEN
         ilazlc = n
      ELSE
*     Now scan each column from the end, returning with the first non-zero.
         DO ilazlc = n, 1, -1
            DO i = 1, m
               IF( a(i, ilazlc).NE.zero ) RETURN
            END DO
         END DO
      END IF
      RETURN