#include "blaswrap.h" #include "f2c.h" /* Subroutine */ int sswap_(integer *n, real *sx, integer *incx, real *sy, integer *incy) { /* System generated locals */ integer i__1; /* Local variables */ static integer i__, m, ix, iy, mp1; static real stemp; /* Purpose ======= interchanges two vectors. uses unrolled loops for increments equal to 1. jack dongarra, linpack, 3/11/78. modified 12/3/93, array(1) declarations changed to array(*) Parameter adjustments */ --sy; --sx; /* Function Body */ if (*n <= 0) { return 0; } 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__ <= i__1; ++i__) { stemp = sx[ix]; sx[ix] = sy[iy]; sy[iy] = stemp; ix += *incx; iy += *incy; /* L10: */ } return 0; /* code for both increments equal to 1 clean-up loop */ L20: m = *n % 3; if (m == 0) { goto L40; } i__1 = m; for (i__ = 1; i__ <= i__1; ++i__) { stemp = sx[i__]; sx[i__] = sy[i__]; sy[i__] = stemp; /* L30: */ } if (*n < 3) { return 0; } L40: mp1 = m + 1; i__1 = *n; for (i__ = mp1; i__ <= i__1; i__ += 3) { stemp = sx[i__]; sx[i__] = sy[i__]; sy[i__] = stemp; stemp = sx[i__ + 1]; sx[i__ + 1] = sy[i__ + 1]; sy[i__ + 1] = stemp; stemp = sx[i__ + 2]; sx[i__ + 2] = sy[i__ + 2]; sy[i__ + 2] = stemp; /* L50: */ } return 0; } /* sswap_ */