opencv/3rdparty/lapack/sasum.c

102 lines
2.3 KiB
C

/* sasum.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"
doublereal sasum_(integer *n, real *sx, integer *incx)
{
/* System generated locals */
integer i__1, i__2;
real ret_val, r__1, r__2, r__3, r__4, r__5, r__6;
/* Local variables */
integer i__, m, mp1, nincx;
real stemp;
/* .. Scalar Arguments .. */
/* .. */
/* .. Array Arguments .. */
/* .. */
/* Purpose */
/* ======= */
/* takes the sum of the absolute values. */
/* uses unrolled loops for increment equal to one. */
/* jack dongarra, linpack, 3/11/78. */
/* modified 3/93 to return if incx .le. 0. */
/* modified 12/3/93, array(1) declarations changed to array(*) */
/* .. Local Scalars .. */
/* .. */
/* .. Intrinsic Functions .. */
/* .. */
/* Parameter adjustments */
--sx;
/* Function Body */
ret_val = 0.f;
stemp = 0.f;
if (*n <= 0 || *incx <= 0) {
return ret_val;
}
if (*incx == 1) {
goto L20;
}
/* code for increment not equal to 1 */
nincx = *n * *incx;
i__1 = nincx;
i__2 = *incx;
for (i__ = 1; i__2 < 0 ? i__ >= i__1 : i__ <= i__1; i__ += i__2) {
stemp += (r__1 = sx[i__], dabs(r__1));
/* L10: */
}
ret_val = stemp;
return ret_val;
/* code for increment equal to 1 */
/* clean-up loop */
L20:
m = *n % 6;
if (m == 0) {
goto L40;
}
i__2 = m;
for (i__ = 1; i__ <= i__2; ++i__) {
stemp += (r__1 = sx[i__], dabs(r__1));
/* L30: */
}
if (*n < 6) {
goto L60;
}
L40:
mp1 = m + 1;
i__2 = *n;
for (i__ = mp1; i__ <= i__2; i__ += 6) {
stemp = stemp + (r__1 = sx[i__], dabs(r__1)) + (r__2 = sx[i__ + 1],
dabs(r__2)) + (r__3 = sx[i__ + 2], dabs(r__3)) + (r__4 = sx[
i__ + 3], dabs(r__4)) + (r__5 = sx[i__ + 4], dabs(r__5)) + (
r__6 = sx[i__ + 5], dabs(r__6));
/* L50: */
}
L60:
ret_val = stemp;
return ret_val;
} /* sasum_ */