LAPACK  3.6.1
LAPACK: Linear Algebra PACKage
integer function ilaslc ( integer  M,
integer  N,
real, dimension( lda, * )  A,
integer  LDA 
)

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

Download ILASLC + dependencies [TGZ] [ZIP] [TXT]

Purpose:
 ILASLC 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 REAL 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
September 2012

Definition at line 80 of file ilaslc.f.

80 *
81 * -- LAPACK auxiliary routine (version 3.4.2) --
82 * -- LAPACK is a software package provided by Univ. of Tennessee, --
83 * -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
84 * September 2012
85 *
86 * .. Scalar Arguments ..
87  INTEGER m, n, lda
88 * ..
89 * .. Array Arguments ..
90  REAL a( lda, * )
91 * ..
92 *
93 * =====================================================================
94 *
95 * .. Parameters ..
96  REAL 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  ilaslc = n
107  ELSE IF( a(1, n).NE.zero .OR. a(m, n).NE.zero ) THEN
108  ilaslc = n
109  ELSE
110 * Now scan each column from the end, returning with the first non-zero.
111  DO ilaslc = n, 1, -1
112  DO i = 1, m
113  IF( a(i, ilaslc).NE.zero ) RETURN
114  END DO
115  END DO
116  END IF
117  RETURN
integer function ilaslc(M, N, A, LDA)
ILASLC scans a matrix for its last non-zero column.
Definition: ilaslc.f:80