125c28e8Piotr Jasiukajtis/*
225c28e8Piotr Jasiukajtis * CDDL HEADER START
325c28e8Piotr Jasiukajtis *
425c28e8Piotr Jasiukajtis * The contents of this file are subject to the terms of the
525c28e8Piotr Jasiukajtis * Common Development and Distribution License (the "License").
625c28e8Piotr Jasiukajtis * You may not use this file except in compliance with the License.
725c28e8Piotr Jasiukajtis *
825c28e8Piotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
925c28e8Piotr Jasiukajtis * or http://www.opensolaris.org/os/licensing.
1025c28e8Piotr Jasiukajtis * See the License for the specific language governing permissions
1125c28e8Piotr Jasiukajtis * and limitations under the License.
1225c28e8Piotr Jasiukajtis *
1325c28e8Piotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each
1425c28e8Piotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
1525c28e8Piotr Jasiukajtis * If applicable, add the following below this CDDL HEADER, with the
1625c28e8Piotr Jasiukajtis * fields enclosed by brackets "[]" replaced with your own identifying
1725c28e8Piotr Jasiukajtis * information: Portions Copyright [yyyy] [name of copyright owner]
1825c28e8Piotr Jasiukajtis *
1925c28e8Piotr Jasiukajtis * CDDL HEADER END
2025c28e8Piotr Jasiukajtis */
2125c28e8Piotr Jasiukajtis/*
2225c28e8Piotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
2325c28e8Piotr Jasiukajtis */
2425c28e8Piotr Jasiukajtis/*
2525c28e8Piotr Jasiukajtis * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
2625c28e8Piotr Jasiukajtis * Use is subject to license terms.
2725c28e8Piotr Jasiukajtis */
2825c28e8Piotr Jasiukajtis
2925c28e8Piotr Jasiukajtis/*
3025c28e8Piotr Jasiukajtis * atan2pi(x) = atan2(x)/pi
3125c28e8Piotr Jasiukajtis */
3225c28e8Piotr Jasiukajtis
3325c28e8Piotr Jasiukajtis#include "libm.h"
3425c28e8Piotr Jasiukajtis
3525c28e8Piotr Jasiukajtisstatic const double invpi = 0.3183098861837906715377675;
3625c28e8Piotr Jasiukajtis
3725c28e8Piotr Jasiukajtisdouble
3825c28e8Piotr Jasiukajtisatan2pi(double y, double x) {
3925c28e8Piotr Jasiukajtis	int	ix, iy;
4025c28e8Piotr Jasiukajtis
4125c28e8Piotr Jasiukajtis	if (x == 0.0 && y == 0.0) {
4225c28e8Piotr Jasiukajtis		ix = ((int *)&x)[HIWORD];
4325c28e8Piotr Jasiukajtis		iy = ((int *)&y)[HIWORD];
4425c28e8Piotr Jasiukajtis		if (ix >= 0)
4525c28e8Piotr Jasiukajtis			return (y);
4625c28e8Piotr Jasiukajtis		return ((iy >= 0)? 1.0 : -1.0);
4725c28e8Piotr Jasiukajtis	}
4825c28e8Piotr Jasiukajtis	return (atan2(y, x) * invpi);
4925c28e8Piotr Jasiukajtis}