* Factorization test suite. */
/*
- * GiNaC Copyright (C) 1999-2016 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2020 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
#include <iostream>
using namespace std;
-static symbol w("w"), x("x"), y("y"), z("z");
-
static unsigned check_factor(const ex& e)
{
ex ee = e.expand();
unsigned result = 0;
ex e;
symbol x("x");
- lst syms;
- syms.append(x);
-
+ lst syms = {x};
+
+ e = 1;
+ result += check_factor(e);
+
e = ex("1+x-x^3", syms);
result += check_factor(e);
return result;
}
-static unsigned check_factorization(const exvector& factors)
+static unsigned check_factor_expanded(const ex& e)
{
- ex e = dynallocate<mul>(factors);
- ex ef = factor(e.expand());
- if (ef.nops() != factors.size()) {
- clog << "wrong number of factors, expected " << factors.size() <<
- ", got " << ef.nops();
+ ex ee = e.expand();
+ ex answer = factor(ee);
+ if ( answer.expand() != ee || (!is_a<mul>(answer) && !is_a<power>(answer)) ) {
+ clog << "factorization of " << e << " == " << ee << " gave wrong result: " << answer << endl;
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()
+static unsigned exam_factor_content()
+{
+ unsigned result = 0;
+ ex e;
+ symbol x("x"), y("y");
+
+ // Fixed 2013-07-28 by Alexei Sheplyakov in factor_univariate().
+ e = ex("174247781*x^2-1989199947807987/200000000000000", lst{x});
+ result += check_factor(e);
+
+ // Fixed 2014-05-18 by Alexei Sheplyakov in factor_multivariate().
+ e = ex("(x+y+x*y)*(3*x+2*y)", lst{x, y});
+ result += check_factor(e);
+
+ return result;
+}
+
+static unsigned exam_factor_wang()
{
- parser reader;
- exvector factors;
- factors.push_back(reader("x+y+x*y"));
- factors.push_back(reader("3*x+2*y"));
- return check_factorization(factors);
+ // these 15 polynomials are from the appendix of P.S.Wang,
+ // "An Improved Multivariate Polynomial Factoring Algorithm"
+ unsigned result = 0;
+ ex e;
+ symbol u("u"), w("w"), x("x"), y("y"), z("z");
+
+ e = ex("(z+x*y+10)*(x*z+y+30)*(y*z+x+20)", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(x^3*(z+y)+y-11)*(x^2*(z^2+y^2)+y+90)", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(y*z^3+x*y*z+y^2+x^3)*(x*(z^4+1)+z+x^3*y^2)", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(z^2-x^3*y+3)*(z^2+x*y^3)*(z^2+x^3*y^4)*(y^4*z^2+x^2*z+5)", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(z^2+x^3*y^4+u^2)*((y^2+x)*z^2+3*u^2*x^3*y^4*z+19*y^2)*(u^2*y^4*z^2+x^2*z+5)", lst{u, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(w^4*z^3-x*y^2*z^2-w^4*x^5*y^6-w^2*x^3*y)*(-x^5*z^3+y*z+x^2*y^3)"
+ "*(w^4*z^6+y^2*z^3-w^2*x^2*y^2*z^2+x^5*z-x^4*y^2-w^3*x^3*y)", lst{w, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(z+y+x-3)^3*(z+y+x-2)^2", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(-15*y^2*z^16+29*w^4*x^12*y^12*z^3+21*x^3*z^2+3*w^15*y^20)"
+ "*(-z^31-w^12*z^20+y^18-y^14+x^2*y^2+x^21+w^2)", lst{w, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("u^4*x*z^2*(6*w^2*y^3*z^2+18*u^2*w^3*x*z^2+15*u*z^2+10*u^2*w*x*y^3)"
+ "*(-44*u*w*x*y^4*z^4-25*u^2*w^3*y*z^4+8*u*w*x^3*z^4-32*u^2*w^4*y^4*z^3"
+ "+48*u^2*x^2*y^3*z^3-12*y^3*z^2+2*u^2*w*x^2*y^2-11*u*w^2*x^3*y-4*w^2*x)", lst{u, w, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(31*u^2*x*z+35*w^2*y^2+6*x*y+40*w*x^2)*(u^2*w^2*x*y^2*z^2+24*u^2*w*x*y^2*z^2"
+ "+12*u^2*x*y^2*z^2+24*u^2*x^2*y*z^2+43*w*x*y*z^2+31*w^2*y*z^2+8*u^2*w^2*z^2"
+ "+44*u*w^2*z^2+37*u^2*y^2*z+41*y^2*z+12*w*x^2*y*z+21*u^2*w*x*y*z+23*x*y*z"
+ "+47*u^2*w^2*z+13*u*w^2*x^2*y^2+22*x*y^2+42*u^2*w^2*y^2+29*w^2*y^2+27*u*w^2*x^2*y"
+ "+37*w^2*x*z+39*u*w*x*z+43*u*x^2*y+24*x*y+9*u^2*w*x^2+22*u^2*w^2)", lst{u, w, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("x*y*(-13*u^3*w^2*x*y*z^3+w^3*z^3+4*u*x*y^2+47*x*y)"
+ "*(43*u*x^3*y^3*z^3+36*u^2*w^3*x*y*z^3+14*w^3*x^3*y^3*z^2-29*w^3*x*y^3*z^2"
+ "-20*u^2*w^2*x^2*y^2*z^2+36*u^2*w*x*y^3*z-48*u*x^3*y^2*z+5*u*w*x^2*y^3"
+ "+36*u*w^2*y^3-9*u*w*y^3-23*u*w*x^3*y^2+46*u*x^3*y^2+8*x*y^2+31*u^2*w^3*y^2"
+ "-9*u^2*y^2+45*x^3-46*u^2*w*x)", lst{u, w, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(z+y+x-3)^3", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(3*z^3+2*w*z-9*y^3-y^2+45*x^3)*(w^2*z^3+47*x*y-w^2)", lst{w, x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("(-18*x^4*y^5+22*y^5-26*x^3*y^4-38*x^2*y^4+29*x^2*y^3-41*x^4*y^2+37*x^4)"
+ "*(33*x^5*y^6+11*y^2+35*x^3*y-22*x^4)", lst{x, y, z});
+ result += check_factor_expanded(e);
+
+ e = ex("x^6*y^3*z^2*(3*z^3+2*w*z-8*x*y^2+14*w^2*y^2-y^2+18*x^3*y)"
+ "*(-12*w^2*x*y*z^3+w^2*z^3+3*x*y^2+29*x-w^2)", lst{w, x, y, z});
+ result += check_factor_expanded(e);
+
+ return result;
}
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;
+ result += exam_factor_content(); cout << '.' << flush;
+ result += exam_factor_wang(); cout << '.' << flush;
return result;
}