1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * CDDL HEADER START
3*0Sstevel@tonic-gate *
4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*0Sstevel@tonic-gate * with the License.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate * and limitations under the License.
13*0Sstevel@tonic-gate *
14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate *
20*0Sstevel@tonic-gate * CDDL HEADER END
21*0Sstevel@tonic-gate */
22*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" /* from UCB 5.2 3/9/86 */
23*0Sstevel@tonic-gate
24*0Sstevel@tonic-gate /*
25*0Sstevel@tonic-gate * the call
26*0Sstevel@tonic-gate * x = frexp(arg,&exp);
27*0Sstevel@tonic-gate * must return a double fp quantity x which is <1.0
28*0Sstevel@tonic-gate * and the corresponding binary exponent "exp".
29*0Sstevel@tonic-gate * such that
30*0Sstevel@tonic-gate * arg = x*2^exp
31*0Sstevel@tonic-gate */
32*0Sstevel@tonic-gate double
frexp(x,i)33*0Sstevel@tonic-gate frexp(x, i)
34*0Sstevel@tonic-gate double x;
35*0Sstevel@tonic-gate int *i;
36*0Sstevel@tonic-gate {
37*0Sstevel@tonic-gate int neg, j;
38*0Sstevel@tonic-gate
39*0Sstevel@tonic-gate j = 0;
40*0Sstevel@tonic-gate neg = 0;
41*0Sstevel@tonic-gate if (x<0) {
42*0Sstevel@tonic-gate x = -x;
43*0Sstevel@tonic-gate neg = 1;
44*0Sstevel@tonic-gate }
45*0Sstevel@tonic-gate if (x>=1.0)
46*0Sstevel@tonic-gate while (x>=1.0) {
47*0Sstevel@tonic-gate j = j+1;
48*0Sstevel@tonic-gate x = x/2;
49*0Sstevel@tonic-gate }
50*0Sstevel@tonic-gate else if (x < 0.5 && x != 0.0)
51*0Sstevel@tonic-gate while(x<0.5) {
52*0Sstevel@tonic-gate j = j-1;
53*0Sstevel@tonic-gate x = 2*x;
54*0Sstevel@tonic-gate }
55*0Sstevel@tonic-gate *i = j;
56*0Sstevel@tonic-gate if(neg)
57*0Sstevel@tonic-gate x = -x;
58*0Sstevel@tonic-gate return (x);
59*0Sstevel@tonic-gate }
60