dasum.c

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/* DASUM.F -- translated by f2c (version 19941215).
   You must link the resulting object file with the libraries:
        -lf2c -lm   (in that order)
*/

#include "f2c.h"
#include "cblasimpexp.h"
doublereal __IMPEXP__ dasum_(n, dx, incx)
integer *n;
doublereal *dx;
integer *incx;
{
    /* System generated locals */
    integer i__1, i__2;
    doublereal ret_val, d__1, d__2, d__3, d__4, d__5, d__6;

    /* Local variables */
    static integer i, m;
    static doublereal dtemp;
    static integer nincx, mp1;


/*     takes the sum of the absolute values. */
/*     jack dongarra, linpack, 3/11/78. */


    /* Parameter adjustments */
    --dx;

    /* Function Body */
    ret_val = 0.;
    dtemp = 0.;
    if (*n <= 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) {
        dtemp += (d__1 = dx[i], abs(d__1));
/* L10: */
    }
    ret_val = dtemp;
    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) {
        dtemp += (d__1 = dx[i], abs(d__1));
/* L30: */
    }
    if (*n < 6) {
        goto L60;
    }
L40:
    mp1 = m + 1;
    i__2 = *n;
    for (i = mp1; i <= i__2; i += 6) {
        dtemp = dtemp + (d__1 = dx[i], abs(d__1)) + (d__2 = dx[i + 1], abs(
                d__2)) + (d__3 = dx[i + 2], abs(d__3)) + (d__4 = dx[i + 3], 
                abs(d__4)) + (d__5 = dx[i + 4], abs(d__5)) + (d__6 = dx[i + 5]
                , abs(d__6));
/* L50: */
    }
L60:
    ret_val = dtemp;
    return ret_val;
} /* dasum_ */

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