3 * Provides some routines for generating expressions that are later used as
4 * input in the consistency checks. */
7 * GiNaC Copyright (C) 1999-2001 Johannes Gutenberg University Mainz, Germany
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24 // For rand() and friends:
29 #ifndef NO_NAMESPACE_GINAC
30 using namespace GiNaC;
31 #endif // ndef NO_NAMESPACE_GINAC
33 /* Create a dense univariate random polynomial in x.
34 * (of the form 9 - 22*a - 17*a^2 + 14*a^3 + 7*a^4 + 7a^5 if degree==5) */
36 dense_univariate_poly(const symbol & x, unsigned degree)
40 for (unsigned i=0; i<=degree; ++i)
41 unipoly += numeric((rand()-RAND_MAX/2))*pow(x,i);
46 /* Create a dense bivariate random polynomial in x1 and x2.
47 * (of the form 9 + 52*x1 - 27*x1^2 + 84*x2 + 7*x2^2 - 12*x1*x2 if degree==2)
50 dense_bivariate_poly(const symbol & x1, const symbol & x2, unsigned degree)
54 for (unsigned i1=0; i1<=degree; ++i1)
55 for (unsigned i2=0; i2<=degree-i1; ++i2)
56 bipoly += numeric((rand()-RAND_MAX/2))*pow(x1,i1)*pow(x2,i2);
61 /* Chose a randum symbol or number from the argument list. */
63 random_symbol(const symbol & x,
70 switch (abs(rand()) % 4) {
82 do { c1 = rand()%20 - 10; } while (!c1);
84 do { c2 = rand()%20 - 10; } while (!c2);
88 if (complex && !(rand()%5))
96 /* Create a sparse random tree in three symbols. */
98 sparse_tree(const symbol & x,
102 bool trig = false, // true includes trigonomatric functions
103 bool rational = true, // false excludes coefficients in Q
104 bool complex = false) // true includes complex numbers
107 return random_symbol(x,y,z,rational,complex);
108 switch (abs(rand()) % 10) {
113 return add(sparse_tree(x,y,z,level-1, trig, rational),
114 sparse_tree(x,y,z,level-1, trig, rational));
118 return mul(sparse_tree(x,y,z,level-1, trig, rational),
119 sparse_tree(x,y,z,level-1, trig, rational));
124 powbase = sparse_tree(x,y,z,level-1, trig, rational);
125 } while (powbase.is_zero());
126 return pow(powbase, abs(rand() % 4));
131 switch (abs(rand()) % 4) {
133 return sin(sparse_tree(x,y,z,level-1, trig, rational));
135 return cos(sparse_tree(x,y,z,level-1, trig, rational));
137 return exp(sparse_tree(x,y,z,level-1, trig, rational));
143 logarg = sparse_tree(x,y,z,level-1, trig, rational);
144 } while (logarg.is_zero());
145 // Keep the evaluator from accidentally plugging an
146 // unwanted I in the tree:
147 if (!complex && logarg.info(info_flags::negative))
150 } while (logex.is_zero());
156 return random_symbol(x,y,z,rational,complex);