opencv/3rdparty/lapack/ilaslr.c

91 lines
2.3 KiB
C

/* ilaslr.f -- translated by f2c (version 20061008).
You must link the resulting object file with libf2c:
on Microsoft Windows system, link with libf2c.lib;
on Linux or Unix systems, link with .../path/to/libf2c.a -lm
or, if you install libf2c.a in a standard place, with -lf2c -lm
-- in that order, at the end of the command line, as in
cc *.o -lf2c -lm
Source for libf2c is in /netlib/f2c/libf2c.zip, e.g.,
http://www.netlib.org/f2c/libf2c.zip
*/
#include "clapack.h"
integer ilaslr_(integer *m, integer *n, real *a, integer *lda)
{
/* System generated locals */
integer a_dim1, a_offset, ret_val, i__1;
/* Local variables */
integer i__, j;
/* -- LAPACK auxiliary routine (version 3.2.1) -- */
/* -- April 2009 -- */
/* -- LAPACK is a software package provided by Univ. of Tennessee, -- */
/* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- */
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* ILASLR scans A for its last non-zero row. */
/* Arguments */
/* ========= */
/* M (input) INTEGER */
/* The number of rows of the matrix A. */
/* N (input) INTEGER */
/* The number of columns of the matrix A. */
/* A (input) REAL array, dimension (LDA,N) */
/* The m by n matrix A. */
/* LDA (input) INTEGER */
/* The leading dimension of the array A. LDA >= max(1,M). */
/* ===================================================================== */
/* .. Parameters .. */
/* .. */
/* .. Local Scalars .. */
/* .. */
/* .. Executable Statements .. */
/* Quick test for the common case where one corner is non-zero. */
/* Parameter adjustments */
a_dim1 = *lda;
a_offset = 1 + a_dim1;
a -= a_offset;
/* Function Body */
if (*m == 0) {
ret_val = *m;
} else if (a[*m + a_dim1] != 0.f || a[*m + *n * a_dim1] != 0.f) {
ret_val = *m;
} else {
/* Scan up each column tracking the last zero row seen. */
ret_val = 0;
i__1 = *n;
for (j = 1; j <= i__1; ++j) {
for (i__ = *m; i__ >= 1; --i__) {
if (a[i__ + j * a_dim1] != 0.f) {
break;
}
}
ret_val = max(ret_val,i__);
}
}
return ret_val;
} /* ilaslr_ */