frexp.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License, Version 1.0 only
* (the "License"). You may not use this file except in compliance
* with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
#pragma ident "%Z%%M% %I% %E% SMI" /* from UCB 5.2 3/9/86 */
/*
* the call
* x = frexp(arg,&exp);
* must return a double fp quantity x which is <1.0
* and the corresponding binary exponent "exp".
* such that
* arg = x*2^exp
*/
double
frexp(x, i)
double x;
int *i;
{
int neg, j;
j = 0;
neg = 0;
if (x<0) {
x = -x;
neg = 1;
}
if (x>=1.0)
while (x>=1.0) {
j = j+1;
x = x/2;
}
else if (x < 0.5 && x != 0.0)
while(x<0.5) {
j = j-1;
x = 2*x;
}
*i = j;
if(neg)
x = -x;
return (x);
}