Improve (fix?) smod: now it really converts into symmetric representation...

[ginac.git] / ginac / inifcns.cpp

diff --git a/ginac/inifcns.cpp b/ginac/inifcns.cpp
index dad9d9e7702b1424300204de0acdc47c967f962b..fa998b234bc1c6ff8968b993b42808188bf4d4a7 100644 (file)
--- a/ginac/inifcns.cpp
+++ b/ginac/inifcns.cpp
@@ -3,7 +3,7 @@
  *  Implementation of GiNaC's initially known functions. */
 
 /*
- *  GiNaC Copyright (C) 1999-2005 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2008 Johannes Gutenberg University Mainz, Germany
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -759,7 +759,7 @@ static ex binomial_sym(const ex & x, const numeric & y)
        if (y.is_integer()) {
                if (y.is_nonneg_integer()) {
                        const unsigned N = y.to_int();
-                       if (N == 0) return _ex0;
+                       if (N == 0) return _ex1;
                        if (N == 1) return x;
                        ex t = x.expand();
                        for (unsigned i = 2; i <= N; ++i)
@@ -884,7 +884,7 @@ ex lsolve(const ex &eqns, const ex &symbols, unsigned options)
        
        // syntax checks
        if (!eqns.info(info_flags::list)) {
-               throw(std::invalid_argument("lsolve(): 1st argument must be a list"));
+               throw(std::invalid_argument("lsolve(): 1st argument must be a list or an equation"));
        }
        for (size_t i=0; i<eqns.nops(); i++) {
                if (!eqns.op(i).info(info_flags::relation_equal)) {
@@ -892,7 +892,7 @@ ex lsolve(const ex &eqns, const ex &symbols, unsigned options)
                }
        }
        if (!symbols.info(info_flags::list)) {
-               throw(std::invalid_argument("lsolve(): 2nd argument must be a list"));
+               throw(std::invalid_argument("lsolve(): 2nd argument must be a list or a symbol"));
        }
        for (size_t i=0; i<symbols.nops(); i++) {
                if (!symbols.op(i).info(info_flags::symbol)) {