1 /** @file paranoia_check.cpp
3 * This set of tests checks for some of GiNaC's oopses which showed up during
4 * development. Things were evaluated wrongly and so. It should not find such
5 * a sick behaviour again. But since we are paranoic and we want to exclude
6 * that behaviour for good... */
9 * GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
26 #include <ginac/ginac.h>
27 using namespace GiNaC;
29 // The very first pair of historic problems had its roots in power.cpp and was
30 // finally resolved on April 27th. (Fixing the first on April 23rd actually
31 // introduced the second.)
32 static unsigned paranoia_check1(void)
35 symbol x("x"), y("y"), z("z");
42 // In the first one expand did not do any job at all:
43 if ( !g.expand().is_equal(x) ) {
44 clog << "e = x*y*z; f = y*z; expand(e/f) erroneously returned "
45 << g.expand() << endl;
49 // This one somehow used to return 0:
51 if (!e.expand().is_equal(e)) {
52 clog << "expand(pow(x + 1, -1)) erroneously returned "
53 << e.expand() << endl;
60 // And here the second oops which showed up until May 17th 1999. It had to do
61 // with lexicographic canonicalization and thus showed up only if the variables
62 // had the names as given here:
63 static unsigned paranoia_check2(void)
66 symbol x("x"), y("y"), z("z");
73 // After .expand(), g should be zero:
74 if (!g.expand().is_equal(exZERO())) {
75 clog << "e = (x + z*x); f = e*y; expand(f - e*y) erroneously returned "
76 << g.expand() << endl;
79 // After .eval(), g should be zero:
80 if (!g.eval().is_equal(exZERO())) {
81 clog << "e = (x + z*x); f = e*y; eval(f - e*y) erroneously returned "
85 // This actually worked already back in April. But we are very paranoic!
86 if (!g.expand().eval().is_equal(exZERO())) {
87 clog << "e = (x + z*x); f = e*y; eval(expand(f - e*y)) erroneously returned "
88 << g.expand().eval() << endl;
95 // The third bug was introduced on May 18, discovered on May 19 and fixed that
96 // same day. It worked when x was substituted by 1 but not with other numbers:
97 static unsigned paranoia_check3(void)
100 symbol x("x"), y("y");
106 if (!f.is_equal(y)) {
107 clog << "e = x*y - y; f = e.subs(x == 2) erroneously returned "
111 if (!f.eval().is_equal(y)) {
112 clog << "e = x*y - y; eval(e.subs(x == 2)) erroneously returned "
116 if (!f.expand().is_equal(y)) {
117 clog << "e = x*y - y; expand(e.subs(x == 2)) erroneously returned "
118 << f.expand() << endl;
125 // The fourth bug was also discovered on May 19 and fixed immediately:
126 static unsigned paranoia_check4(void)
132 e = pow(x, 2) + x + 1;
133 f = pow(x, 2) + x + 1;
136 if (!g.is_equal(exZERO())) {
137 clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g erroneously returned "
141 if (!g.is_equal(exZERO())) {
142 clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g.eval() erroneously returned "
150 // The fifth oops was discovered on May 20 and fixed a day later:
151 static unsigned paranoia_check5(void)
154 symbol x("x"), y("y");
158 f = pow(x, 2) * pow(y, 2) + 2*x*y + 1;
160 if (!(e-f).expand().is_equal(exZERO())) {
161 clog << "e = pow(x*y+1,2); f = pow(x,2)*pow(y,2) + 2*x*y + 1; (e-f).expand() erroneously returned "
162 << (e-f).expand() << endl;
169 // This one was discovered on Jun 1 and fixed the same day:
170 static unsigned paranoia_check6(void)
179 if (!f.is_equal(pow(x, 5))) {
180 clog << "e = pow(x, -5); f = e.denom(); f was " << f << " (should be x^5)" << endl;
186 // This one was introduced on June 1 by some aggressive manual optimization.
187 // Discovered and fixed on June 2.
188 static unsigned paranoia_check7(void)
191 symbol x("x"), y("y");
194 ex f = expand(pow(e, 2) - (e*y*(x + 1)));
197 clog << "e=y+y*x+2; f=expand(pow(e,2)-(e*y*(x+1))) has "
198 << f.nops() << " arguments instead of 3 ( f=="
199 << f << " )" << endl;
205 // This one was a result of the rewrite of mul::max_coefficient when we
206 // introduced the overall_coefficient field in expairseq objects on Oct 1.
208 static unsigned paranoia_check8(void)
216 // The bug caused a division by zero in normal(), so the following
217 // check is actually bogus...
218 if (!f.is_equal(e)) {
219 clog << "normal(-x/(x+1)) returns " << f << " instead of -x/(x+1)\n";
225 unsigned paranoia_check(void)
229 cout << "checking several ex-bugs just out of pure paranoia..." << flush;
230 clog << "---------several ex-bugs just out of pure paranoia:" << endl;
232 result += paranoia_check1();
233 result += paranoia_check2();
234 result += paranoia_check3();
235 result += paranoia_check4();
236 result += paranoia_check5();
237 result += paranoia_check6();
238 result += paranoia_check7();
239 result += paranoia_check8();
243 clog << "(no output)" << endl;