X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=check%2Fgenex.cpp;h=f4bffb151a484d5b87129833a9dd634e7f253db5;hp=77ea18fdb0d89da8afa3f0062f129c7f9476b0d7;hb=c69d2c6f95cd62f1bbf2ff665551b1d1b693466c;hpb=f4ea690a3f118bf364190f0ef3c3f6d2ccdf6206

diff --git a/check/genex.cpp b/check/genex.cpp
index 77ea18fd..f4bffb15 100644
--- a/check/genex.cpp
+++ b/check/genex.cpp
@@ -1,10 +1,10 @@
 /** @file genex.cpp
  *
- *  Provides some routines for generating expressions that are later used as input
- *  in the consistency checks. */
+ *  Provides some routines for generating expressions that are later used as 
+ *  input in the consistency checks. */
 
 /*
- *  GiNaC Copyright (C) 1999-2000 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2001 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
@@ -25,34 +25,131 @@
 #include <stdlib.h>
 
 #include "ginac.h"
-
-#ifndef NO_NAMESPACE_GINAC
 using namespace GiNaC;
-#endif // ndef NO_NAMESPACE_GINAC
 
 /* Create a dense univariate random polynomial in x.
  * (of the form 9 - 22*a - 17*a^2 + 14*a^3 + 7*a^4 + 7a^5 if degree==5) */
 const ex
 dense_univariate_poly(const symbol & x, unsigned degree)
 {
-    ex unipoly;
-    
-    for (unsigned i=0; i<=degree; ++i)
-        unipoly += numeric((rand()-RAND_MAX/2))*pow(x,i);
-    
-    return unipoly;
+	ex unipoly;
+	
+	for (unsigned i=0; i<=degree; ++i)
+		unipoly += numeric((rand()-RAND_MAX/2))*pow(x,i);
+	
+	return unipoly;
 }
 
 /* Create a dense bivariate random polynomial in x1 and x2.
- * (of the form 9 + 52*x1 - 27*x1^2 + 84*x2 + 7*x2^2 - 12*x1*x2 if degree ==2) */
+ * (of the form 9 + 52*x1 - 27*x1^2 + 84*x2 + 7*x2^2 - 12*x1*x2 if degree==2)
+ */
 const ex
 dense_bivariate_poly(const symbol & x1, const symbol & x2, unsigned degree)
 {
-    ex bipoly;
-    
-    for (unsigned i1=0; i1<=degree; ++i1)
-        for (unsigned i2=0; i2<=degree-i1; ++i2)
-            bipoly += numeric((rand()-RAND_MAX/2))*pow(x1,i1)*pow(x2,i2);
-    
-    return bipoly;
+	ex bipoly;
+	
+	for (unsigned i1=0; i1<=degree; ++i1)
+		for (unsigned i2=0; i2<=degree-i1; ++i2)
+			bipoly += numeric((rand()-RAND_MAX/2))*pow(x1,i1)*pow(x2,i2);
+	
+	return bipoly;
+}
+
+/* Chose a randum symbol or number from the argument list. */
+const ex
+random_symbol(const symbol & x,
+			  const symbol & y,
+			  const symbol & z,
+			  bool rational = true,
+			  bool complex = false)
+{
+	ex e;
+	switch (abs(rand()) % 4) {
+		case 0:
+			e = x;
+			break;
+		case 1:
+			e = y;
+			break;
+		case 2:
+			e = z;
+			break;
+		case 3: {
+			int c1;
+			do { c1 = rand()%20 - 10; } while (!c1);
+			int c2;
+			do { c2 = rand()%20 - 10; } while (!c2);
+			if (!rational)
+				c2 = 1;
+			e = numeric(c1, c2);
+			if (complex && !(rand()%5))
+				e = e*I;
+			break;
+		}
+	}
+	return e;
+}
+
+/* Create a sparse random tree in three symbols. */
+const ex
+sparse_tree(const symbol & x,
+			const symbol & y,
+			const symbol & z,
+			int level,
+			bool trig = false,	// true includes trigonomatric functions
+			bool rational = true, // false excludes coefficients in Q
+			bool complex = false) // true includes complex numbers
+{
+	if (level == 0)
+		return random_symbol(x,y,z,rational,complex);
+	switch (abs(rand()) % 10) {
+		case 0:
+		case 1:
+		case 2:
+		case 3:
+			return add(sparse_tree(x,y,z,level-1, trig, rational),
+					   sparse_tree(x,y,z,level-1, trig, rational));
+		case 4:
+		case 5:
+		case 6:
+			return mul(sparse_tree(x,y,z,level-1, trig, rational),
+					   sparse_tree(x,y,z,level-1, trig, rational));
+		case 7:
+		case 8: {
+			ex powbase;
+			do {
+				powbase = sparse_tree(x,y,z,level-1, trig, rational);
+			} while (powbase.is_zero());
+			return pow(powbase, abs(rand() % 4));
+			break;
+		}
+		case 9:
+			if (trig) {
+				switch (abs(rand()) % 4) {
+					case 0:
+						return sin(sparse_tree(x,y,z,level-1, trig, rational));
+					case 1:
+						return cos(sparse_tree(x,y,z,level-1, trig, rational));
+					case 2:
+						return exp(sparse_tree(x,y,z,level-1, trig, rational));
+					case 3: {
+						ex logex;
+						do {
+							ex logarg;
+							do {
+								logarg = sparse_tree(x,y,z,level-1, trig, rational);
+							} while (logarg.is_zero());
+							// Keep the evaluator from accidentally plugging an
+							// unwanted I in the tree:
+							if (!complex && logarg.info(info_flags::negative))
+								logarg = -logarg;
+							logex = log(logarg);
+						} while (logex.is_zero());
+						return logex;
+						break;
+					}
+				}
+			} else
+				return random_symbol(x,y,z,rational,complex);
+	}
 }