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1*> \brief \b ILADLC
2*
3*  =========== DOCUMENTATION ===========
4*
5* Online html documentation available at
6*            http://www.netlib.org/lapack/explore-html/
7*
8*> \htmlonly
9*> Download ILADLC + dependencies
10*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/iladlc.f">
11*> [TGZ]</a>
12*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/iladlc.f">
13*> [ZIP]</a>
14*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/iladlc.f">
15*> [TXT]</a>
16*> \endhtmlonly
17*
18*  Definition:
19*  ===========
20*
21*       INTEGER FUNCTION ILADLC( M, N, A, LDA )
22*
23*       .. Scalar Arguments ..
24*       INTEGER            M, N, LDA
25*       ..
26*       .. Array Arguments ..
27*       DOUBLE PRECISION   A( LDA, * )
28*       ..
29*
30*
31*> \par Purpose:
32*  =============
33*>
34*> \verbatim
35*>
36*> ILADLC scans A for its last non-zero column.
37*> \endverbatim
38*
39*  Arguments:
40*  ==========
41*
42*> \param[in] M
43*> \verbatim
44*>          M is INTEGER
45*>          The number of rows of the matrix A.
46*> \endverbatim
47*>
48*> \param[in] N
49*> \verbatim
50*>          N is INTEGER
51*>          The number of columns of the matrix A.
52*> \endverbatim
53*>
54*> \param[in] A
55*> \verbatim
56*>          A is DOUBLE PRECISION array, dimension (LDA,N)
57*>          The m by n matrix A.
58*> \endverbatim
59*>
60*> \param[in] LDA
61*> \verbatim
62*>          LDA is INTEGER
63*>          The leading dimension of the array A. LDA >= max(1,M).
64*> \endverbatim
65*
66*  Authors:
67*  ========
68*
69*> \author Univ. of Tennessee
70*> \author Univ. of California Berkeley
71*> \author Univ. of Colorado Denver
72*> \author NAG Ltd.
73*
74*> \date November 2011
75*
76*> \ingroup auxOTHERauxiliary
77*
78*  =====================================================================
79      INTEGER FUNCTION ILADLC( M, N, A, LDA )
80*
81*  -- LAPACK auxiliary routine (version 3.4.0) --
82*  -- LAPACK is a software package provided by Univ. of Tennessee,    --
83*  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
84*     November 2011
85*
86*     .. Scalar Arguments ..
87      INTEGER            M, N, LDA
88*     ..
89*     .. Array Arguments ..
90      DOUBLE PRECISION   A( LDA, * )
91*     ..
92*
93*  =====================================================================
94*
95*     .. Parameters ..
96      DOUBLE PRECISION ZERO
97      PARAMETER ( ZERO = 0.0D+0 )
98*     ..
99*     .. Local Scalars ..
100      INTEGER I
101*     ..
102*     .. Executable Statements ..
103*
104*     Quick test for the common case where one corner is non-zero.
105      IF( N.EQ.0 ) THEN
106         ILADLC = N
107      ELSE IF( A(1, N).NE.ZERO .OR. A(M, N).NE.ZERO ) THEN
108         ILADLC = N
109      ELSE
110*     Now scan each column from the end, returning with the first non-zero.
111         DO ILADLC = N, 1, -1
112            DO I = 1, M
113               IF( A(I, ILADLC).NE.ZERO ) RETURN
114            END DO
115         END DO
116      END IF
117      RETURN
118      END
119