f2clib.c

来自「局域网ICQ的源代码」· C语言 代码 · 共 80 行

/*

$Log: f2clib.c,v $
Revision 1.1.1.1  2002/07/28 05:23:47  freeman_yong
lpc10 codec

 * Revision 1.1  1996/08/19  22:32:10  jaf
 * Initial revision
 *

*/

/*
 * f2clib.c
 *
 * SCCS ID:  @(#)f2clib.c 1.2 96/05/19
 */

#include "f2c.h"

#ifdef KR_headers
integer pow_ii(ap, bp) integer *ap, *bp;
#else
integer pow_ii(integer *ap, integer *bp)
#endif
{
	integer pow, x, n;
	unsigned long u;

	x = *ap;
	n = *bp;

	if (n <= 0) {
		if (n == 0 || x == 1)
			return 1;
		if (x != -1)
			return x == 0 ? 1/x : 0;
		n = -n;
		}
	u = n;
	for(pow = 1; ; )
		{
		if(u & 01)
			pow *= x;
		if(u >>= 1)
			x *= x;
		else
			break;
		}
	return(pow);
	}



#ifdef KR_headers
double r_sign(a,b) real *a, *b;
#else
double r_sign(real *a, real *b)
#endif
{
double x;
x = (*a >= 0 ? *a : - *a);
return( *b >= 0 ? x : -x);
}



#ifdef KR_headers
double floor();
integer i_nint(x) real *x;
#else
#undef abs
#include "math.h"
integer i_nint(real *x)
#endif
{
return( (*x)>=0 ?
	floor(*x + .5) : -floor(.5 - *x) );
}