From 17ee7a6d0c88cd9b33db41fbca2973177b9a8a2f Mon Sep 17 00:00:00 2001
From: Richard Kreckel <Richard.Kreckel@uni-mainz.de>
Date: Thu, 16 Aug 2001 22:47:54 +0000
Subject: [PATCH] - doc update: motivate use of .expand() in basic::series().

---
 NEWS              |  1 +
 configure.in      |  6 +++---
 ginac/pseries.cpp | 14 ++++++++------
 3 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/NEWS b/NEWS
index ba6b6e18..0698b906 100644
--- a/NEWS
+++ b/NEWS
@@ -1,6 +1,7 @@
 This file records noteworthy changes.
 
 0.9.3 (<insert date>)
+* series expansion now much more consistent for small order expansion.
 * lsolve() accepts an algorithmic hint as parameter.
 
 0.9.2 (31 July 2001)
diff --git a/configure.in b/configure.in
index 77fdcbef..837448b8 100644
--- a/configure.in
+++ b/configure.in
@@ -19,9 +19,9 @@ dnl (don't we all *love* M4?)...
 
 GINACLIB_MAJOR_VERSION=0
 GINACLIB_MINOR_VERSION=9
-GINACLIB_MICRO_VERSION=2
-GINACLIB_INTERFACE_AGE=1
-GINACLIB_BINARY_AGE=1
+GINACLIB_MICRO_VERSION=3
+GINACLIB_INTERFACE_AGE=0
+GINACLIB_BINARY_AGE=0
 GINACLIB_VERSION=$GINACLIB_MAJOR_VERSION.$GINACLIB_MINOR_VERSION.$GINACLIB_MICRO_VERSION
 
 AC_SUBST(GINACLIB_MAJOR_VERSION)
diff --git a/ginac/pseries.cpp b/ginac/pseries.cpp
index 0fae94bc..7ae30a9c 100644
--- a/ginac/pseries.cpp
+++ b/ginac/pseries.cpp
@@ -499,21 +499,23 @@ ex basic::series(const relational & r, int order, unsigned options) const
 	
 	int n;
 	for (n=1; n<order; ++n) {
-		fac = fac.mul(numeric(n));
+		fac = fac.mul(n);
+		// We need to test for zero in order to see if the series terminates.
+		// The problem is that there is no such thing as a perfect test for
+		// zero.  Expanding the term occasionally helps a little...
 		deriv = deriv.diff(s).expand();
-		if (deriv.is_zero()) {
-			// Series terminates
+		if (deriv.is_zero())  // Series terminates
 			return pseries(r, seq);
-		}
+
 		coeff = deriv.subs(r);
 		if (!coeff.is_zero())
-			seq.push_back(expair(fac.inverse() * coeff, numeric(n)));
+			seq.push_back(expair(fac.inverse() * coeff, n));
 	}
 	
 	// Higher-order terms, if present
 	deriv = deriv.diff(s);
 	if (!deriv.expand().is_zero())
-		seq.push_back(expair(Order(_ex1()), numeric(n)));
+		seq.push_back(expair(Order(_ex1()), n));
 	return pseries(r, seq);
 }
 
-- 
2.44.0