/* -- translated by f2c (version 19940927).
You must link the resulting object file with the libraries:
-lf2c -lm (in that order)
*/
#include "f2c.h"
real sdot_(integer *n, real *sx, integer *incx, real *sy, integer *incy)
{
/* System generated locals */
integer i__1;
real ret_val;
/* Local variables */
static integer i, m;
static real stemp;
static integer ix, iy, mp1;
/* forms the dot product of two vectors.
uses unrolled loops for increments equal to one.
jack dongarra, linpack, 3/11/78.
modified 12/3/93, array(1) declarations changed to array(*)
Parameter adjustments
Function Body */
#define SY(I) sy[(I)-1]
#define SX(I) sx[(I)-1]
stemp = 0.f;
ret_val = 0.f;
if (*n <= 0) {
return ret_val;
}
if (*incx == 1 && *incy == 1) {
goto L20;
}
/* code for unequal increments or equal increments
not equal to 1 */
ix = 1;
iy = 1;
if (*incx < 0) {
ix = (-(*n) + 1) * *incx + 1;
}
if (*incy < 0) {
iy = (-(*n) + 1) * *incy + 1;
}
i__1 = *n;
for (i = 1; i <= *n; ++i) {
stemp += SX(ix) * SY(iy);
ix += *incx;
iy += *incy;
/* L10: */
}
ret_val = stemp;
return ret_val;
/* code for both increments equal to 1
clean-up loop */
L20:
m = *n % 5;
if (m == 0) {
goto L40;
}
i__1 = m;
for (i = 1; i <= m; ++i) {
stemp += SX(i) * SY(i);
/* L30: */
}
if (*n < 5) {
goto L60;
}
L40:
mp1 = m + 1;
i__1 = *n;
for (i = mp1; i <= *n; i += 5) {
stemp = stemp + SX(i) * SY(i) + SX(i + 1) * SY(i + 1) + SX(i + 2) *
SY(i + 2) + SX(i + 3) * SY(i + 3) + SX(i + 4) * SY(i + 4);
/* L50: */
}
L60:
ret_val = stemp;
return ret_val;
} /* sdot_ */