#include "clapack.h" /* Subroutine */ int dscal_(integer *n, doublereal *da, doublereal *dx, integer *incx) { /* System generated locals */ integer i__1, i__2; /* Local variables */ integer i__, m, mp1, nincx; /* .. Scalar Arguments .. */ /* .. */ /* .. Array Arguments .. */ /* .. */ /* Purpose */ /* ======= */ /* * */ /* scales a vector by a constant. */ /* 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 */ --dx; /* Function Body */ if (*n <= 0 || *incx <= 0) { return 0; } 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) { dx[i__] = *da * dx[i__]; /* L10: */ } return 0; /* code for increment equal to 1 */ /* clean-up loop */ L20: m = *n % 5; if (m == 0) { goto L40; } i__2 = m; for (i__ = 1; i__ <= i__2; ++i__) { dx[i__] = *da * dx[i__]; /* L30: */ } if (*n < 5) { return 0; } L40: mp1 = m + 1; i__2 = *n; for (i__ = mp1; i__ <= i__2; i__ += 5) { dx[i__] = *da * dx[i__]; dx[i__ + 1] = *da * dx[i__ + 1]; dx[i__ + 2] = *da * dx[i__ + 2]; dx[i__ + 3] = *da * dx[i__ + 3]; dx[i__ + 4] = *da * dx[i__ + 4]; /* L50: */ } return 0; } /* dscal_ */