From: Jens Vollinga <jensv@nikhef.nl>
Date: Thu, 25 Mar 2010 09:36:41 +0000 (+0100)
Subject: Fixed a bug in atan2. It gave a division by zero error for calls like
X-Git-Tag: release_1-5-7~3
X-Git-Url: https://ginac.de/ginac.git/static/gitweb.css/ginac.git?a=commitdiff_plain;h=eff5558e5d0c6dcc70883962ed3a72a1cc6ad03b;p=ginac.git

Fixed a bug in atan2. It gave a division by zero error for calls like
atan2(-Pi,0), because arguments like -Pi were not recognized (via
info_flags) as negative but as real nevertheless.
(cherry picked from commit 9e13d46552bb7852399867b9eb355732b9ded59e)
---

diff --git a/ginac/inifcns_trans.cpp b/ginac/inifcns_trans.cpp
index 39931dcd..3f161d21 100644
--- a/ginac/inifcns_trans.cpp
+++ b/ginac/inifcns_trans.cpp
@@ -842,7 +842,7 @@ static ex atan2_eval(const ex & y, const ex & x)
 			return _ex1_2*Pi;
 
 		// atan(y, 0), y real and negative -> -Pi/2
-		if (y.info(info_flags::negative))
+		if (y.info(info_flags::real) && !y.is_zero())
 			return _ex_1_2*Pi;
 	}