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...
8 * GiNaC Copyright (C) 1999 Johannes Gutenberg University Mainz, Germany
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
25 #include <ginac/ginac.h>
27 // The very first pair of historic problems had its roots in power.cpp and was
28 // finally resolved on April 27th. (Fixing the first on April 23rd actually
29 // introduced the second.)
30 static unsigned paranoia_check1(void)
33 symbol x("x"), y("y"), z("z");
40 // In the first one expand did not do any job at all:
41 if ( !g.expand().is_equal(x) ) {
42 clog << "e = x*y*z; f = y*z; expand(e/f) erroneously returned "
43 << g.expand() << endl;
47 // This one somehow used to return 0:
49 if (!e.expand().is_equal(e)) {
50 clog << "expand(pow(x + 1, -1)) erroneously returned "
51 << e.expand() << endl;
58 // And here the second oops which showed up until May 17th 1999. It had to do
59 // with lexicographic canonicalization and thus showed up only if the variables
60 // had the names as given here:
61 static unsigned paranoia_check2(void)
64 symbol x("x"), y("y"), z("z");
71 // After .expand(), g should be zero:
72 if (!g.expand().is_equal(exZERO())) {
73 clog << "e = (x + z*x); f = e*y; expand(f - e*y) erroneously returned "
74 << g.expand() << endl;
77 // After .eval(), g should be zero:
78 if (!g.eval().is_equal(exZERO())) {
79 clog << "e = (x + z*x); f = e*y; eval(f - e*y) erroneously returned "
83 // This actually worked already back in April. But we are very paranoic!
84 if (!g.expand().eval().is_equal(exZERO())) {
85 clog << "e = (x + z*x); f = e*y; eval(expand(f - e*y)) erroneously returned "
86 << g.expand().eval() << endl;
93 // The third bug was introduced on May 18, discovered on May 19 and fixed that
94 // same day. It worked when x was substituted by 1 but not with other numbers:
95 static unsigned paranoia_check3(void)
98 symbol x("x"), y("y");
104 if (!f.is_equal(y)) {
105 clog << "e = x*y - y; f = e.subs(x == 2) erroneously returned "
109 if (!f.eval().is_equal(y)) {
110 clog << "e = x*y - y; eval(e.subs(x == 2)) erroneously returned "
114 if (!f.expand().is_equal(y)) {
115 clog << "e = x*y - y; expand(e.subs(x == 2)) erroneously returned "
116 << f.expand() << endl;
123 // The fourth bug was also discovered on May 19 and fixed immediately:
124 static unsigned paranoia_check4(void)
130 e = pow(x, 2) + x + 1;
131 f = pow(x, 2) + x + 1;
134 if (!g.is_equal(exZERO())) {
135 clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g erroneously returned "
139 if (!g.is_equal(exZERO())) {
140 clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g.eval() erroneously returned "
148 // The fifth oops was discovered on May 20 and fixed a day later:
149 static unsigned paranoia_check5(void)
152 symbol x("x"), y("y");
156 f = pow(x, 2) * pow(y, 2) + 2*x*y + 1;
158 if (!(e-f).expand().is_equal(exZERO())) {
159 clog << "e = pow(x*y+1,2); f = pow(x,2)*pow(y,2) + 2*x*y + 1; (e-f).expand() erroneously returned "
160 << (e-f).expand() << endl;
167 // This one was discovered on Jun 1 and fixed the same day:
168 static unsigned paranoia_check6(void)
177 if (!f.is_equal(pow(x, 5))) {
178 clog << "e = pow(x, -5); f = e.denom(); f was " << f << " (should be x^5)" << endl;
184 // This one was introduced on June 1 by some aggressive manual optimization.
185 // Discovered and fixed on June 2.
186 static unsigned paranoia_check7(void)
189 symbol x("x"), y("y");
192 ex f = expand(pow(e, 2) - (e*y*(x + 1)));
195 clog << "e=y+y*x+2; f=expand(pow(e,2)-(e*y*(x+1))) has "
196 << f.nops() << " arguments instead of 3 ( f=="
197 << f << " )" << endl;
203 // This one was a result of the rewrite of mul::max_coefficient when we
204 // introduced the overall_coefficient field in expairseq objects on Oct 1.
206 static unsigned paranoia_check8(void)
214 // The bug caused a division by zero in normal(), so the following
215 // check is actually bogus...
216 if (!f.is_equal(e)) {
217 clog << "normal(-x/(x+1)) returns " << f << " instead of -x/(x+1)\n";
223 unsigned paranoia_check(void)
227 cout << "checking several ex-bugs just out of pure paranoia..." << flush;
228 clog << "---------several ex-bugs just out of pure paranoia:" << endl;
230 result += paranoia_check1();
231 result += paranoia_check2();
232 result += paranoia_check3();
233 result += paranoia_check4();
234 result += paranoia_check5();
235 result += paranoia_check6();
236 result += paranoia_check7();
237 result += paranoia_check8();
241 clog << "(no output)" << endl;