Fix an infinite loop in factor_multivariate.

[ginac.git] / check / exam_factor.cpp

diff --git a/check/exam_factor.cpp b/check/exam_factor.cpp
index e3552bfcdd8e0aaa1cd7f8ccb4f5f065e4269582..9696a2b531daf372094e5c8e8ab4bda60894d683 100644 (file)
--- a/check/exam_factor.cpp
+++ b/check/exam_factor.cpp
@@ -3,7 +3,7 @@
  *  Factorization test suite. */
 
 /*
- *  GiNaC Copyright (C) 1999-2008 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2011 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
@@ -20,11 +20,12 @@
  *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
-#include <iostream>
 #include "ginac.h"
-using namespace std;
 using namespace GiNaC;
 
+#include <iostream>
+using namespace std;
+
 static symbol w("w"), x("x"), y("y"), z("z");
 
 static unsigned check_factor(const ex& e)
@@ -41,7 +42,7 @@ static unsigned check_factor(const ex& e)
 static unsigned exam_factor1()
 {
        unsigned result = 0;
-       ex e, d;
+       ex e;
        symbol x("x");
        lst syms;
        syms.append(x);
@@ -110,7 +111,7 @@ static unsigned exam_factor1()
 static unsigned exam_factor2()
 {
        unsigned result = 0;
-       ex e, d;
+       ex e;
        symbol x("x"), y("y"), z("z");
        lst syms;
        syms = x, y, z;
@@ -118,15 +119,98 @@ static unsigned exam_factor2()
        e = ex("x+y", syms);
        result += check_factor(e);
 
-       e = ex("x+y", syms);
+       e = ex("(x^2-y+1)*(x+y)", syms);
        result += check_factor(e);
 
        e = ex("-2*(x+y)*(x-y)", syms);
        result += check_factor(e);
 
+       e = ex("(16+x^2*z^3)*(-17+3*x-5*z)*(2*x+3*z)*(x-y^2-z^3)", syms);
+       result += check_factor(e);
+
+       e = ex("(x-y*z)*(x-y^2-z^3)*(x+y+z)", syms);
+       result += check_factor(e);
+       
+       e = ex("-(y^2-x+z^3)*x*(x+y+z)", syms);
+       result += check_factor(e);
+       
+       e = ex("-316*(3*x-4*z)*(2*x+3*z)*(x+y)*(-1+x)", syms);
+       result += check_factor(e);
+       
+       e = ex("(x+x^3+z^2)*(3*x-4*z)", syms);
+       result += check_factor(e);
+       
+       e = ex("250*(-3+x)*(4*z-3*x)*(x^3+z^2+x)*x", syms);
+       result += check_factor(e);
+       
+       e = ex("327*(x+z^2+x^3)*(3*x-4*z)*(-7+5*x-x^3)*(1+x+x^2)", syms);
+       result += check_factor(e);
+       
+       e = ex("x-y^2-z^3", syms);
+       result += check_factor(e);
+       
+       e = ex("-390*(7+3*x^4)*(2+x^2)*(x-z^3-y^2)", syms);
+       result += check_factor(e);
+       
+       e = ex("55*(1+x)^2*(3*x-4*z)*(1+x+x^2)*(x+x^3+z^2)", syms);
+       result += check_factor(e);
+       
+       e = ex("x+y*x-1", syms);
+       result += check_factor(e);
+       
+       e = ex("390*(-1+x^6-x)*(7+3*x^4)*(2+x^2)*(y+x)*(-1+y-x^2)*(1+x^2+x)^2", syms);
+       result += check_factor(e);
+       
+       e = ex("310*(y+x)*(-1+y-x^2)", syms);
+       result += check_factor(e);
+
+       return result;
+}
+
+static unsigned exam_factor3()
+{
+       unsigned result = 0;
+       ex e;
+       symbol k("k"), n("n");
+       lst syms;
+       syms = k, n;
+       
+       e = ex("1/2*(-3+3*k-n)*(-2+3*k-n)*(-1+3*k-n)", syms);
+       result += check_factor(e);
+
+       e = ex("1/4*(2*k-n)*(-1+2*k-n)", syms);
+       result += check_factor(e);
+
        return result;
 }
 
+static unsigned check_factorization(const exvector& factors)
+{
+       ex e = (new mul(factors))->setflag(status_flags::dynallocated);
+       ex ef = factor(e.expand());
+       if (ef.nops() != factors.size()) {
+               clog << "wrong number of factors, expected " << factors.size() <<
+                       ", got " << ef.nops();
+               return 1;
+       }
+       for (size_t i = 0; i < ef.nops(); ++i) {
+               if (find(factors.begin(), factors.end(), ef.op(i)) == factors.end()) {
+                       clog << "wrong factorization: term not found: " << ef.op(i);
+                       return 1;
+               }
+       }
+       return 0;
+}
+
+static unsigned factor_integer_content_bug()
+{
+       parser reader;
+       exvector factors;
+       factors.push_back(reader("x+y+x*y"));
+       factors.push_back(reader("3*x+2*y"));
+       return check_factorization(factors);
+}
+
 unsigned exam_factor()
 {
        unsigned result = 0;
@@ -135,6 +219,9 @@ unsigned exam_factor()
 
        result += exam_factor1(); cout << '.' << flush;
        result += exam_factor2(); cout << '.' << flush;
+       result += exam_factor3(); cout << '.' << flush;
+       result += factor_integer_content_bug();
+       cout << '.' << flush;
 
        return result;
 }