3 * Provides some routines for generating expressions that are later used as
4 * input in the consistency checks. */
7 * GiNaC Copyright (C) 1999-2004 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
27 using namespace GiNaC;
29 /* Create a dense univariate random polynomial in x.
30 * (of the form 9 - 22*a - 17*a^2 + 14*a^3 + 7*a^4 + 7a^5 if degree==5) */
32 dense_univariate_poly(const symbol & x, unsigned degree)
36 for (unsigned i=0; i<=degree; ++i)
37 unipoly += numeric((rand()-RAND_MAX/2))*pow(x,i);
42 /* Create a dense bivariate random polynomial in x1 and x2.
43 * (of the form 9 + 52*x1 - 27*x1^2 + 84*x2 + 7*x2^2 - 12*x1*x2 if degree==2)
46 dense_bivariate_poly(const symbol & x1, const symbol & x2, unsigned degree)
50 for (unsigned i1=0; i1<=degree; ++i1)
51 for (unsigned i2=0; i2<=degree-i1; ++i2)
52 bipoly += numeric((rand()-RAND_MAX/2))*pow(x1,i1)*pow(x2,i2);
57 /* Chose a randum symbol or number from the argument list. */
59 random_symbol(const symbol & x,
66 switch (abs(rand()) % 4) {
78 do { c1 = rand()%20 - 10; } while (!c1);
80 do { c2 = rand()%20 - 10; } while (!c2);
84 if (complex && !(rand()%5))
92 /* Create a sparse random tree in three symbols. */
94 sparse_tree(const symbol & x,
98 bool trig = false, // true includes trigonomatric functions
99 bool rational = true, // false excludes coefficients in Q
100 bool complex = false) // true includes complex numbers
103 return random_symbol(x,y,z,rational,complex);
104 switch (abs(rand()) % 10) {
109 return add(sparse_tree(x,y,z,level-1, trig, rational),
110 sparse_tree(x,y,z,level-1, trig, rational));
114 return mul(sparse_tree(x,y,z,level-1, trig, rational),
115 sparse_tree(x,y,z,level-1, trig, rational));
120 powbase = sparse_tree(x,y,z,level-1, trig, rational);
121 } while (powbase.is_zero());
122 return pow(powbase, abs(rand() % 4));
127 switch (abs(rand()) % 4) {
129 return sin(sparse_tree(x,y,z,level-1, trig, rational));
131 return cos(sparse_tree(x,y,z,level-1, trig, rational));
133 return exp(sparse_tree(x,y,z,level-1, trig, rational));
139 logarg = sparse_tree(x,y,z,level-1, trig, rational);
140 } while (logarg.is_zero());
141 // Keep the evaluator from accidentally plugging an
142 // unwanted I in the tree:
143 if (!complex && logarg.info(info_flags::negative))
146 } while (logex.is_zero());
152 return random_symbol(x,y,z,rational,complex);