/** @file exam_paranoia.cpp
*
* This set of tests checks for some of GiNaC's oopses which showed up during
- * development. Things were evaluated wrongly and so. Such a sick behaviour
+ * development. Things were evaluated wrongly and so. Such a sick behavior
* shouldn't occur any more. But we are paranoic and we want to exclude these
* these oopses for good, so we run those stupid tests... */
/*
- * GiNaC Copyright (C) 1999-2011 Johannes Gutenberg University Mainz, Germany
+ * GiNaC Copyright (C) 1999-2021 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
f = e*y;
g = f - e*y;
- // After .expand(), g should be zero:
- if (!g.expand().is_zero()) {
- clog << "e = (x + z*x); f = e*y; expand(f - e*y) erroneously returned "
- << g.expand() << endl;
- ++result;
- }
// After .eval(), g should be zero:
- if (!g.eval().is_zero()) {
- clog << "e = (x + z*x); f = e*y; eval(f - e*y) erroneously returned "
- << g.eval() << endl;
- ++result;
- }
- // This actually worked already back in April 1999.
- // But we are *very* paranoic!
- if (!g.expand().eval().is_zero()) {
- clog << "e = (x + z*x); f = e*y; eval(expand(f - e*y)) erroneously returned "
- << g.expand().eval() << endl;
+ if (!g.is_zero()) {
+ clog << "e = (x + z*x); f = e*y; g = (f - e*y) erroneously returned g == "
+ << g << endl;
++result;
}
<< f << endl;
++result;
}
- if (!f.eval().is_equal(y)) {
- clog << "e = x*y - y; eval(e.subs(x == 2)) erroneously returned "
- << f.eval() << endl;
- ++result;
- }
- if (!f.expand().is_equal(y)) {
- clog << "e = x*y - y; expand(e.subs(x == 2)) erroneously returned "
- << f.expand() << endl;
- ++result;
- }
return result;
}
<< g << endl;
++result;
}
- if (!g.is_zero()) {
- clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g.eval() erroneously returned "
- << g.eval() << endl;
- ++result;
- }
return result;
}
ex r;
try {
- r = pow(b,e).eval();
+ r = pow(b, e);
if (!(r-2*sqrt(ex(2))).is_zero()) {
clog << "2^(3/2) erroneously returned " << r << " instead of 2*sqrt(2)" << endl;
++result;
}
// Bug in add::eval() could result in numeric terms not being collected into
-// the overall coefficient. Fixed on Sep 22, 2010
+// the overall coefficient. Fixed first on Sep 22, 2010 and again on Dec 17 2015
static unsigned exam_paranoia18()
{
+ unsigned result = 0;
+
ex sqrt2 = sqrt(ex(2));
- ex e = 1+2*(sqrt2+1)*(sqrt2-1);
- if ( e.real_part() != 3 ) {
+ ex e1 = 1 + 2*(sqrt2+1)*(sqrt2-1);
+ if (e1.real_part() != 3) {
clog << "real_part(1+2*(sqrt(2)+1)*(sqrt(2)-1)) failed to evaluate to 3\n";
- return 1;
+ ++result;
}
- return 0;
+
+ ex sqrt3 = sqrt(ex(3));
+ ex e2 = 2 + 2*(sqrt2+1)*(sqrt2-1) - 2*(sqrt3+1)*(sqrt3-1);
+ if (e2.real_part() != 0) {
+ clog << "real_part(2+2*(sqrt(2)+1)*(sqrt(2)-1)-3*(sqrt(3)+1)*(sqrt(3)-1)) failed to evaluate to 0\n";
+ ++result;
+ }
+
+ return result;
}
// Bug in mul::conjugate when factors are evaluated at branch cuts, reported as
return 0;
}
+// Bugs in is_polynomial (fixed 2011-05-20 and 2014-07-26).
+static unsigned exam_paranoia20()
+{
+ unsigned result = 0;
+ symbol x("x"), y("y");
+ ex e1 = sqrt(x*x+1)*sqrt(x+1);
+ if (e1.is_polynomial(x)) {
+ clog << "sqrt(x*x+1)*sqrt(x+1) is wrongly reported to be a polynomial in x\n";
+ ++result;
+ }
+ ex e2 = sqrt(Pi)*x;
+ if (!e2.is_polynomial(x)) {
+ clog << "sqrt(Pi)*x is wrongly reported to be no polynomial in x\n";
+ ++result;
+ }
+ ex e3 = sqrt(x);
+ if (!e3.is_polynomial(y)) {
+ clog << "sqrt(x) is wrongly reported to be no polynomial in y\n";
+ ++result;
+ }
+ ex e4 = (1+y)/(2+x);
+ if (e4.is_polynomial(x)) {
+ clog << "(1+y)/(2+x) is wrongly reported to be a polynomial in x\n";
+ ++result;
+ }
+ return result;
+}
+
+static unsigned exam_mul_info()
+{
+ symbol x("x"), y("y");
+ ex e = x*y;
+ if (!e.info(info_flags::indefinite)) {
+ clog << "eek, product of two symbols is NOT indefinite\n";
+ return 1;
+ }
+ return 0;
+}
+
+static unsigned is_polynomial_false_positive()
+{
+ unsigned result = 0;
+ symbol x("x"), n("n");
+ exvector nonpoly_exprs;
+ nonpoly_exprs.push_back(1/(1-x));
+ nonpoly_exprs.push_back(1/(x+1));
+ nonpoly_exprs.push_back(-1/(x-1));
+ nonpoly_exprs.push_back(1/(1-x*x));
+ nonpoly_exprs.push_back(1/(1-pow(x,n)));
+ nonpoly_exprs.push_back(x-1/(x-1));
+ for (exvector::const_iterator ep = nonpoly_exprs.begin();
+ ep != nonpoly_exprs.end(); ++ep) {
+ if (ep->is_polynomial(x)) {
+ clog << "(" << *ep << ").is_polynomial(" << x << ") "
+ "erroneously returned true" << endl;
+ ++result;
+ }
+ }
+ return result;
+}
+
+// Bug in power::expand reported by Isuru Fernando (fixed 2015-05-07).
+static unsigned exam_paranoia21()
+{
+ symbol x("x");
+ ex e = pow(x + sqrt(ex(2))*x, 2).expand();
+ if (e.nops() != 2) {
+ clog << "(x+sqrt(2)*x)^2 was wrongly expanded to " << e << "\n";
+ return 1;
+ }
+ return 0;
+}
+
+// Bug in power::expand (fixed 2015-07-18).
+static unsigned exam_paranoia22()
+{
+ symbol x("x"), y("y");
+ ex e = pow(sqrt(1+x)+y*sqrt(1+x), 2).expand();
+ if (e.nops() != 6) {
+ clog << "(sqrt(1+x)+y*sqrt(1+x))^2 was wrongly expanded to " << e << "\n";
+ return 1;
+ }
+ return 0;
+}
+
+// Bug in expairseq::evalchildren().
+static unsigned exam_paranoia23()
+{
+ unsigned result = 0;
+ symbol x("x");
+
+ epvector v1;
+ v1.push_back(expair(1, 1));
+ v1.push_back(expair(2*x, -1));
+ ex e1 = add(v1); // Should be e==1-2*x,
+ if (!e1.is_equal(1-2*x)) {
+ clog << "Failure constructing " << e1 << " from add.\n";
+ ++result;
+ }
+
+ epvector v2;
+ v2.push_back(expair(x, 1));
+ v2.push_back(expair(1,-1));
+ ex e2 = mul(v2); // Should be e==x;
+ if (!e2.is_equal(x)) {
+ clog << "Failure constructing " << e2 << " from mul.\n";
+ ++result;
+ }
+
+ return result;
+}
+
+// Bug in add ctor
+unsigned exam_paranoia24()
+{
+ symbol a("a"), b("b"), c("c");
+ ex e = -a + 2*b + c;
+
+ if (e.diff(c).nops() > 1) {
+ clog << "diff(" << e << ",c) was not fully evaluated.\n";
+ return 1;
+ }
+ return 0;
+}
+
+// Bug in partial fraction expansion
+unsigned exam_paranoia25()
+{
+ symbol x("x");
+ ex ex1=pow(x,4)/(x-1)/4;
+ ex ex2=sqrfree_parfrac(ex1,x);
+ ex e = (ex1-ex2).normal();
+
+ if (! e.is_zero()) {
+ clog << "partial fraction expansion of " << ex1 << " produces error.\n";
+ return 1;
+ }
+ return 0;
+}
+
+// Bug in power expansion
+unsigned exam_paranoia26()
+{
+ unsigned result = 0;
+ symbol x("x"), y("y"), a("a");
+ possymbol s("s"), t("t");
+ exmap pwrs =
+ { {pow((x+1)*(y-2)*(s-3)*(t+4), a), pow((x+1)*(y-2)*(s-3), a)*pow(t+4, a)},
+ {pow(2*(x+1)*(y-2)*(s-3)*(t+4), a), pow(2,a)*pow((x+1)*(y-2)*(s-3), a)*pow(t+4, a)},
+ {pow(-(x+1)*(y-2)*(s-3)*(t+4), a), pow(-(x+1)*(y-2)*(s-3), a)*pow(t+4, a)},
+ {pow(-2*(x+1)*(y-2)*(s-3)*(t+4), a), pow(2,a)*pow(-(x+1)*(y-2)*(s-3), a)*pow(t+4, a)} };
+
+ for (auto e : pwrs) {
+ if (! (e.first.expand()).is_equal(e.second) ) {
+ clog << "power expansion of " << e.first << " produces error.\n";
+ ++result;
+ }
+ }
+
+ return result;
+}
+
+// Bug in collect()
+// cf. https://www.ginac.de/pipermail/ginac-list/2021-March/002337.html
+static unsigned exam_collect_multiply_referenced_lst()
+{
+ unsigned result = 0;
+ symbol x("x"), y("y");
+ ex a = x + y;
+ ex l = lst{x, y};
+ ex l2 = l; // make l a multiply referenced object
+
+ try {
+ ex b = collect(a, l);
+ } catch (const std::runtime_error & e) {
+ clog << "collect(" << ", " << l << ") threw a runtime_error("
+ << e.what() << ")" << endl;
+ ++result;
+ }
+
+ return result;
+}
+
unsigned exam_paranoia()
{
unsigned result = 0;
result += exam_paranoia17(); cout << '.' << flush;
result += exam_paranoia18(); cout << '.' << flush;
result += exam_paranoia19(); cout << '.' << flush;
+ result += exam_paranoia20(); cout << '.' << flush;
+ result += exam_mul_info(); cout << '.' << flush;
+ result += is_polynomial_false_positive(); cout << '.' << flush;
+ result += exam_paranoia21(); cout << '.' << flush;
+ result += exam_paranoia22(); cout << '.' << flush;
+ result += exam_paranoia23(); cout << '.' << flush;
+ result += exam_paranoia24(); cout << '.' << flush;
+ result += exam_paranoia25(); cout << '.' << flush;
+ result += exam_paranoia26(); cout << '.' << flush;
+ result += exam_collect_multiply_referenced_lst(); cout << '.' << flush;
return result;
}