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#include "blaswrap.h"
#include "f2c.h"
integer idamax_(integer *n, doublereal *dx, integer *incx)
{
/* System generated locals */
integer ret_val, i__1;
doublereal d__1;
/* Local variables */
static doublereal dmax__;
static integer i__, ix;
/* finds the index of element having max. absolute value.
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(*)
Parameter adjustments */
--dx;
/* Function Body */
ret_val = 0;
if (*n < 1 || *incx <= 0) {
return ret_val;
}
ret_val = 1;
if (*n == 1) {
return ret_val;
}
if (*incx == 1) {
goto L20;
}
/* code for increment not equal to 1 */
ix = 1;
dmax__ = abs(dx[1]);
ix += *incx;
i__1 = *n;
for (i__ = 2; i__ <= i__1; ++i__) {
if ((d__1 = dx[ix], abs(d__1)) <= dmax__) {
goto L5;
}
ret_val = i__;
dmax__ = (d__1 = dx[ix], abs(d__1));
L5:
ix += *incx;
/* L10: */
}
return ret_val;
/* code for increment equal to 1 */
L20:
dmax__ = abs(dx[1]);
i__1 = *n;
for (i__ = 2; i__ <= i__1; ++i__) {
if ((d__1 = dx[i__], abs(d__1)) <= dmax__) {
goto L30;
}
ret_val = i__;
dmax__ = (d__1 = dx[i__], abs(d__1));
L30:
;
}
return ret_val;
} /* idamax_ */
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