X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=check%2Fexam_misc.cpp;h=4127a32710f59b6b9c3919e0336dc20de3d2f111;hp=8052bda95804a4948fa8ccba6a2672fe33037050;hb=e2627379c98aeafae903cc2f04bdbdc9defa34f7;hpb=af922d5eb36ed70e4a9e3ffaf4c24492cf89a1a6

diff --git a/check/exam_misc.cpp b/check/exam_misc.cpp
index 8052bda9..4127a327 100644
--- a/check/exam_misc.cpp
+++ b/check/exam_misc.cpp
@@ -3,7 +3,7 @@
  */
 
 /*
- *  GiNaC Copyright (C) 1999-2000 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2003 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
@@ -24,25 +24,22 @@
 #include "exams.h"
 
 #define VECSIZE 30
-static unsigned exam_expand_subs(void)
+static unsigned exam_expand_subs()
 {
 	unsigned result = 0;
-	symbol a1("a1");
 	symbol a[VECSIZE];
 	ex e, aux;
 	
-	a[1] = a1;
-	for (unsigned i=0; i<VECSIZE; ++i) {
+	for (unsigned i=0; i<VECSIZE; ++i)
 		e = e + a[i];
-	}
 	
 	// prepare aux so it will swallow anything but a1^2:
 	aux = -e + a[0] + a[1];
 	e = expand(subs(expand(pow(e, 2)), a[0] == aux));
 	
-	if (e != pow(a1,2)) {
+	if (e != pow(a[1],2)) {
 		clog << "Denny Fliegner's quick consistency check erroneously returned "
-			 << e << "." << endl;
+		     << e << "." << endl;
 		++result;
 	}
 	
@@ -54,7 +51,7 @@ static unsigned exam_expand_subs(void)
  *  2)  expand e
  *  3)  substitute a0 by -a1 in e
  *  after which e should return 0 (without expanding). */
-static unsigned exam_expand_subs2(void)
+static unsigned exam_expand_subs2()
 {
 	unsigned result = 0;
 	symbol a("a"), b("b");
@@ -65,14 +62,209 @@ static unsigned exam_expand_subs2(void)
 	
 	if (f != 0) {
 		clog << "e = pow(a+b,200).expand(); f = e.subs(a == -b); erroneously returned "
-			 << f << " instead of simplifying to 0." << endl;
+		     << f << " instead of simplifying to 0." << endl;
+		++result;
+	}
+	
+	return result;
+}
+
+static unsigned exam_expand_power()
+{
+	unsigned result = 0;
+	symbol x("x"), a("a"), b("b");
+	ex e;
+	
+	e = pow(x,pow(a+b,2)-pow(a,2)-pow(b,2)-a*b*2).expand();
+	
+	if (e != 1) {
+		clog << "e = pow(x,pow(a+b,2)-pow(a,2)-pow(b,2)-a*b*2).expand(); erroneously returned "
+		     << e << " instead of simplifying to 1." << endl;
+		++result;
+	}
+	
+	return result;
+}
+
+static unsigned exam_sqrfree()
+{
+	unsigned result = 0;
+	symbol x("x"), y("y");
+	ex e1, e2;
+	
+	e1 = (1+x)*pow((2+x),2)*pow((3+x),3)*pow((4+x),4);
+	e2 = sqrfree(expand(e1),lst(x));
+	if (e1 != e2) {
+		clog << "sqrfree(expand(" << e1 << ")) erroneously returned "
+		     << e2 << endl;
+		++result;
+	}
+	
+	e1 = (x+y)*pow((x+2*y),2)*pow((x+3*y),3)*pow((x+4*y),4);
+	e2 = sqrfree(expand(e1));
+	if (e1 != e2) {
+		clog << "sqrfree(expand(" << e1 << ")) erroneously returned "
+		     << e2 << endl;
+		++result;
+	}
+	e2 = sqrfree(expand(e1),lst(x));
+	if (e1 != e2) {
+		clog << "sqrfree(expand(" << e1 << "),[x]) erroneously returned "
+		     << e2 << endl;
+		++result;
+	}
+	e2 = sqrfree(expand(e1),lst(y));
+	if (e1 != e2) {
+		clog << "sqrfree(expand(" << e1 << "),[y]) erroneously returned "
+		     << e2 << endl;
+		++result;
+	}
+	e2 = sqrfree(expand(e1),lst(x,y));
+	if (e1 != e2) {
+		clog << "sqrfree(expand(" << e1 << "),[x,y]) erroneously returned "
+		     << e2 << endl;
+		++result;
+	}
+	
+	return result;
+}
+
+/* Arithmetic Operators should behave just as one expects from built-in types.
+ * When somebody screws up the operators this routine will most probably fail
+ * to compile.  Unfortunately we can only test the stuff that is allowed, not
+ * what is forbidden (e.g. e1+e2 = 42) since that must not compile.  :-(   */
+static unsigned exam_operator_semantics()
+{
+	unsigned result = 0;
+	ex e1, e2;
+	int i1, i2;
+	
+	// Assignment should not return const ex though it may be obfuscated:
+	e1 = 7; e2 = 4;
+	i1 = 7; i2 = 4;
+	(e1 = e2) = 2;
+	(i1 = i2) = 2;
+	if (e1!=i1 || e2!=i2) {
+		clog << "Semantics of ex::operator=() screwed." << endl;
+		++result;
+	}
+	(e1 += e2) = 2;
+	(i1 += i2) = 2;
+	if (e1!=i1 || e2!=i2) {
+		clog << "Semantics of ex::operator=() screwed." << endl;
+		++result;
+	}
+	(e1 -= e2) = 2;
+	(i1 -= i2) = 2;
+	if (e1!=i1 || e2!=i2) {
+		clog << "Semantics of ex::operator=() screwed." << endl;
+		++result;
+	}
+	
+	// Prefix/postfix increment/decrement behaviour:
+	e1 = 7; e2 = 4;
+	i1 = 7; i2 = 4;
+	e1 = (--e2 = 2)++;
+	i1 = (--i2 = 2)++;
+	if (e1!=i1 || e2!=i2) {
+		clog << "Semantics of increment/decrement operators screwed." << endl;
+		++result;
+	}
+	e1 = (++e2 = 2)--;
+	i1 = (++i2 = 2)--;
+	if (e1!=i1 || e2!=i2) {
+		clog << "Semantics of increment/decrement operators screwed." << endl;
+		++result;
+	}
+	
+	// prefix increment/decrement must return an lvalue (contrary to postfix):
+	e1 = 7; e2 = 4;
+	i1 = 7; i2 = 4;
+	--++----e1;  ++(++++++++(++++e2));
+	--++----i1;  ++(++++++++(++++i2));
+	if (e1!=i1 || e2!=i2) {
+		clog << "Semantics of prefix increment/decrement operators screwed." << endl;
+		++result;
+	}
+	
+	// This one has a good chance of detecting problems in self-assignment:
+	// (which incidentally was severely broken from version 0.7.3 to 0.8.2).
+	ex selfprobe = numeric("65536");
+	selfprobe = selfprobe;
+	if (!is_exactly_a<numeric>(selfprobe)) {
+		clog << "ex (of numeric) after self-assignment became " << selfprobe << endl;
+		++result;
+	}
+	
+	return result;
+}
+
+/* This checks whether subs() works as intended in some special cases. */
+static unsigned exam_subs()
+{
+	unsigned result = 0;
+	symbol x("x");
+	ex e1, e2;
+
+	// This used to fail in GiNaC 1.0.5 because it first substituted
+	// x+1 -> (x-1)+1 -> x, and then substituted again x -> x-1, giving
+	// the wrong result
+	e1 = x+1;
+	e2 = e1.subs(x == x-1);
+	if (!e2.is_equal(x)) {
+		clog << "(x+1).subs(x==x-1) erroneously returned " << e2 << " instead of x" << endl;
+		++result;
+	}
+
+	e1 = sin(1+sin(x));
+	e2 = e1.subs(sin(wild()) == cos(wild()));
+	if (!e2.is_equal(cos(1+cos(x)))) {
+		clog << "sin(1+sin(x)).subs(sin($1)==cos($1)) erroneously returned " << e2 << " instead of cos(1+cos(x))" << endl;
+		++result;
+	}
+
+	return result;
+}
+
+/* Joris van der Hoeven (he of TeXmacs fame) is a funny guy.  He has his own
+ * ideas what a symbolic system should do.  Let's make sure we won't disappoint
+ * him some day.  Incidentally, this seems to always have worked. */
+static unsigned exam_joris()
+{
+	unsigned result = 0;
+	symbol x("x");
+
+	ex e = expand(pow(x, x-1) * x);
+	if (e != pow(x, x)) {
+		clog << "x^(x-1)*x did not expand to x^x.  Please call Joris!" << endl;
+		++result;
+	}
+
+	return result;
+}
+
+/* Test Chris Dams' algebraic substitutions. */
+static unsigned exam_subs_algebraic()
+{
+	unsigned result = 0;
+	symbol x("x"), y("y");
+
+	ex e = ex(x*x*x*y*y).subs(x*y==2, subs_options::subs_algebraic);
+	if (e != 4*x) {
+		clog << "(x^3*y^2).subs(x*y==2,subs_options::subs_algebraic) erroneously returned " << e << endl;
+		++result;
+	}
+
+	e = ex(x*x*x*x*x).subs(x*x==y, subs_options::subs_algebraic);
+	if (e != y*y*x) {
+		clog << "x^5.subs(x^2==y,subs_options::subs_algebraic) erroneously returned " << e << endl;
 		++result;
 	}
 	
 	return result;
 }
 
-unsigned exam_misc(void)
+unsigned exam_misc()
 {
 	unsigned result = 0;
 	
@@ -81,6 +273,12 @@ unsigned exam_misc(void)
 	
 	result += exam_expand_subs();  cout << '.' << flush;
 	result += exam_expand_subs2();  cout << '.' << flush;
+	result += exam_expand_power(); cout << '.' << flush;
+	result += exam_sqrfree(); cout << '.' << flush;
+	result += exam_operator_semantics(); cout << '.' << flush;
+	result += exam_subs(); cout << '.' << flush;
+	result += exam_joris(); cout << '.' << flush;
+	result += exam_subs_algebraic(); cout << '.' << flush;
 	
 	if (!result) {
 		cout << " passed " << endl;