X-Git-Url: https://www.ginac.de/ginac.git//ginac.git?p=ginac.git;a=blobdiff_plain;f=check%2Fexam_paranoia.cpp;h=d96cda59c035b0a37443b9719b370bd56cd75f0f;hp=104e20da9207f7b5f07ccddb7f305107691c1ab8;hb=c3a7dda76e171bbd1e1418b3dab56df49920f721;hpb=1353ebadf30ce51e5c38f60b13668b6a261f8d5b

diff --git a/check/exam_paranoia.cpp b/check/exam_paranoia.cpp
index 104e20da..d96cda59 100644
--- a/check/exam_paranoia.cpp
+++ b/check/exam_paranoia.cpp
@@ -1,12 +1,12 @@
 /** @file exam_paranoia.cpp
  *
  *  This set of tests checks for some of GiNaC's oopses which showed up during
- *  development.  Things were evaluated wrongly and so.  Such a sick behaviour
+ *  development.  Things were evaluated wrongly and so.  Such a sick behavior
  *  shouldn't occur any more.  But we are paranoic and we want to exclude these
  *  these oopses for good, so we run those stupid tests... */
 
 /*
- *  GiNaC Copyright (C) 1999-2002 Johannes Gutenberg University Mainz, Germany
+ *  GiNaC Copyright (C) 1999-2020 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
@@ -20,15 +20,19 @@
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  */
 
-#include "exams.h"
+#include "ginac.h"
+using namespace GiNaC;
+
+#include <iostream>
+using namespace std;
 
 // The very first pair of historic problems had its roots in power.cpp and was
 // finally resolved on April 27th 1999. (Fixing the first on April 23rd
 // actually introduced the second.)
-static unsigned exam_paranoia1(void)
+static unsigned exam_paranoia1()
 {
 	unsigned result = 0;
 	symbol x("x"), y("y"), z("z");
@@ -59,7 +63,7 @@ static unsigned exam_paranoia1(void)
 // And here the second oops which showed up until May 17th 1999.  It had to do
 // with lexicographic canonicalization and thus showed up only if the variables
 // had the names as given here:
-static unsigned exam_paranoia2(void)
+static unsigned exam_paranoia2()
 {
 	unsigned result = 0;
 	symbol x("x"), y("y"), z("z");
@@ -69,23 +73,10 @@ static unsigned exam_paranoia2(void)
 	f = e*y;
 	g = f - e*y;
 
-	// After .expand(), g should be zero:
-	if (!g.expand().is_zero()) {
-		clog << "e = (x + z*x); f = e*y; expand(f - e*y) erroneously returned "
-		     << g.expand() << endl;
-		++result;
-	}
 	// After .eval(), g should be zero:
-	if (!g.eval().is_zero()) {
-		clog << "e = (x + z*x); f = e*y; eval(f - e*y) erroneously returned "
-		     << g.eval() << endl;
-		++result;
-	}
-	// This actually worked already back in April 1999.
-	// But we are *very* paranoic!
-	if (!g.expand().eval().is_zero()) {
-		clog << "e = (x + z*x); f = e*y; eval(expand(f - e*y)) erroneously returned "
-		     << g.expand().eval() << endl;
+	if (!g.is_zero()) {
+		clog << "e = (x + z*x); f = e*y; g = (f - e*y) erroneously returned g == "
+		     << g << endl;
 		++result;
 	}
 
@@ -95,7 +86,7 @@ static unsigned exam_paranoia2(void)
 // The third bug was introduced on May 18th 1999, discovered on May 19 and
 // fixed that same day.  It worked when x was substituted by 1 but not with
 // other numbers:
-static unsigned exam_paranoia3(void)
+static unsigned exam_paranoia3()
 {
 	unsigned result = 0;
 	symbol x("x"), y("y");
@@ -109,22 +100,12 @@ static unsigned exam_paranoia3(void)
 		     << f << endl;
 		++result;
 	}
-	if (!f.eval().is_equal(y)) {
-		clog << "e = x*y - y; eval(e.subs(x == 2)) erroneously returned "
-		     << f.eval() << endl;
-		++result;
-	}
-	if (!f.expand().is_equal(y)) {
-		clog << "e = x*y - y; expand(e.subs(x == 2)) erroneously returned "
-		     << f.expand() << endl;
-		++result;
-	}
 
 	return result;
 }
 
 // The fourth bug was also discovered on May 19th 1999 and fixed immediately:
-static unsigned exam_paranoia4(void)
+static unsigned exam_paranoia4()
 {
 	unsigned result = 0;
 	symbol x("x");
@@ -139,17 +120,12 @@ static unsigned exam_paranoia4(void)
 		     << g << endl;
 		++result;
 	}
-	if (!g.is_zero()) {
-		clog << "e = pow(x,2) + x + 1; f = pow(x,2) + x + 1; g = e-f; g.eval() erroneously returned "
-		     << g.eval() << endl;
-		++result;
-	}
 
 	return result;
 }
 
 // The fifth oops was discovered on May 20th 1999 and fixed a day later:
-static unsigned exam_paranoia5(void)
+static unsigned exam_paranoia5()
 {
 	unsigned result = 0;
 	symbol x("x"), y("y");
@@ -168,7 +144,7 @@ static unsigned exam_paranoia5(void)
 }
 
 // This one was discovered on Jun 1st 1999 and fixed the same day:
-static unsigned exam_paranoia6(void)
+static unsigned exam_paranoia6()
 {
 	unsigned result = 0;
 	symbol x("x");
@@ -186,7 +162,7 @@ static unsigned exam_paranoia6(void)
 
 // This one was introduced on June 1st 1999 by some aggressive manual
 // optimization. Discovered and fixed on June 2nd.
-static unsigned exam_paranoia7(void)
+static unsigned exam_paranoia7()
 {
 	unsigned result = 0;
 	symbol x("x"), y("y");
@@ -206,7 +182,7 @@ static unsigned exam_paranoia7(void)
 // This one was a result of the rewrite of mul::max_coefficient when we
 // introduced the overall_coefficient field in expairseq objects on Oct 1st
 // 1999. Fixed on Oct 4th.
-static unsigned exam_paranoia8(void)
+static unsigned exam_paranoia8()
 {
 	unsigned result = 0;
 	symbol x("x");
@@ -232,7 +208,7 @@ static unsigned exam_paranoia8(void)
 // Z[X]. multiply_lcm() forgot to multiply the x-linear term with the LCM of
 // the coefficient's denominators (2 in this case).  Introduced on Jan 25th
 // 2000 and fixed on Jan 31th.
-static unsigned exam_paranoia9(void)
+static unsigned exam_paranoia9()
 {
 	unsigned result = 0;
 	symbol x("x");
@@ -251,7 +227,7 @@ static unsigned exam_paranoia9(void)
 // and on Feb 13th 2000 I found out that things like 2^(3/2) throw an exception
 // "power::eval(): pow(0,0) is undefined" instead of simplifying to 2*2^(1/2).
 // It was fixed that same day.
-static unsigned exam_paranoia10(void)
+static unsigned exam_paranoia10()
 {
 	unsigned result = 0;
 	
@@ -260,7 +236,7 @@ static unsigned exam_paranoia10(void)
 	ex r;
 	
 	try {
-		r = pow(b,e).eval();
+		r = pow(b, e);
 		if (!(r-2*sqrt(ex(2))).is_zero()) {
 			clog << "2^(3/2) erroneously returned " << r << " instead of 2*sqrt(2)" << endl;
 			++result;
@@ -276,14 +252,14 @@ static unsigned exam_paranoia10(void)
 // add::normal() forgot to multiply the denominator of the overall_coeff of
 // its expanded and normalized children with the denominator of the expanded
 // child (did you get this? Well, never mind...). Fixed on Feb 21th 2000.
-static unsigned exam_paranoia11(void)
+static unsigned exam_paranoia11()
 {
 	unsigned result = 0;
 	symbol x("x");
 
 	ex e = ((-5-2*x)-((2-5*x)/(-2+x))*(3+2*x))/(5-4*x);
 	ex f = e.normal();
-	ex d = (4+10*x+8*pow(x,2))/(x-2)/(5-4*x);
+	ex d = normal((4+10*x+8*pow(x,2))/(x-2)/(5-4*x));
 
 	if (!(f - d).expand().is_zero()) {
 		clog << "normal(" << e << ") returns " << f << " instead of " << d << endl;
@@ -295,7 +271,7 @@ static unsigned exam_paranoia11(void)
 // This one returned 0 because add::normal() incorrectly assumed that if the
 // common denominator is 1, all the denominators would be 1 (they can in fact
 // be +/-1). Fixed on Aug 2nd 2000.
-static unsigned exam_paranoia12(void)
+static unsigned exam_paranoia12()
 {
 	unsigned result = 0;
 	symbol x("x");
@@ -314,7 +290,7 @@ static unsigned exam_paranoia12(void)
 
 // This one caused a division by 0 because heur_gcd() didn't check its
 // input polynomials against 0. Fixed on Aug 4th 2000.
-static unsigned exam_paranoia13(void)
+static unsigned exam_paranoia13()
 {
 	unsigned result = 0;
 	symbol a("a"), b("b"), c("c");
@@ -338,7 +314,7 @@ static unsigned exam_paranoia13(void)
 
 // A bug introduced on July 19, 2001. quo() and rem() would sometimes call
 // vector::reserve() with a negative argument. Fixed on Dec 20, 2001.
-static unsigned exam_paranoia14(void)
+static unsigned exam_paranoia14()
 {
 	unsigned result = 0;
 	symbol x("x");
@@ -354,7 +330,7 @@ static unsigned exam_paranoia14(void)
 
 // Under certain conditions, power::expand_add_2() could produce non-canonical
 // numeric expairs. Fixed on Oct 24, 2002.
-static unsigned exam_paranoia15(void)
+static unsigned exam_paranoia15()
 {
 	unsigned result = 0;
 
@@ -362,7 +338,7 @@ static unsigned exam_paranoia15(void)
 	// this used to produce "1+4*sqrt(2)+4*2" which would never evaluate
 	// to "9+4*sqrt(2)"
 
-	if (!(q-9-4*pow(2, numeric(1, 2).is_zero()) {
+	if (!(q-9-4*pow(2, numeric(1, 2))).is_zero()) {
 		clog << "expand((sqrt(2)*2+1)^2) erroneously returned " << q << " instead of 9-4*sqrt(2)\n";
 		++result;
 	}
@@ -370,12 +346,301 @@ static unsigned exam_paranoia15(void)
 	return result;
 }
 
-unsigned exam_paranoia(void)
+// Expanding products containing powers of sums could return results that
+// were not fully expanded. Fixed on Dec 10, 2003.
+static unsigned exam_paranoia16()
+{
+	unsigned result = 0;
+	symbol a("a"), b("b"), c("c"), d("d"), e("e");
+	ex e1, e2, e3;
+
+	e1 = pow(1+a*sqrt(b+c), 2);
+	e2 = e1.expand();
+
+	if (e2.has(pow(a, 2)*(b+c))) {
+		clog << "expand(" << e1 << ") didn't fully expand\n";
+		++result;
+	}
+
+	e1 = (d*sqrt(a+b)+a*sqrt(c+d))*(b*sqrt(a+b)+a*sqrt(c+d));
+	e2 = e1.expand();
+
+	if (e2.has(pow(a, 2)*(c+d))) {
+		clog << "expand(" << e1 << ") didn't fully expand\n";
+		++result;
+	}
+
+	e1 = (a+sqrt(b+c))*sqrt(b+c)*(d+sqrt(b+c));
+	e2 = e1.expand();
+
+	if (e2.has(a*(b+c))) {
+		clog << "expand(" << e1 << ") didn't fully expand\n";
+		++result;
+	}
+
+	e1 = pow(sqrt(a+b)+sqrt(c+d), 3);
+	e2 = e1.expand();
+
+	if (e2.has(3*(a+b)*sqrt(c+d)) || e2.has(3*(c+d)*sqrt(a+b))) {
+		clog << "expand(" << e1 << ") didn't fully expand\n";
+		++result;
+	}
+
+	e1 = a*(b+c*(d+e));
+	e2 = e1.expand();
+
+	if (e2.has(c*(d+e))) {
+		clog << "expand(" << e1 << ") didn't fully expand\n";
+		++result;
+	}
+
+	e1 = 2*pow(1+a, 2)/a;
+	e2 = e1.expand();
+
+	if (e2.has(pow(a, 2))) {
+		clog << "expand(" << e1 << ") didn't fully expand\n";
+		++result;
+	}
+
+	e1 = a*(a+b);
+	e2 = pow(pow(e1, -1), -1);
+
+	if (e2.has(a*b)) {
+		clog << "double reciprocal expanded where it should not\n";
+		++result;
+	}
+
+	return result;
+}
+
+// Bug in reposition_dummy_indices() could result in correct expression
+// turned into one with inconsistent indices. Fixed on Aug 29, 2006
+static unsigned exam_paranoia17()
+{
+	varidx mu1(symbol("mu1"), 4);
+	varidx mu2(symbol("mu2"), 4);
+	varidx mu3(symbol("mu3"), 4);
+	varidx mu4(symbol("mu4"), 4);
+	varidx mu5(symbol("mu5"), 4);
+	varidx mu6(symbol("mu6"), 4);
+
+	exvector ev2;
+	ev2.push_back(mu3.toggle_variance());
+	ev2.push_back(mu6);
+	ev2.push_back(mu5.toggle_variance());
+	ev2.push_back(mu6.toggle_variance());
+	ev2.push_back(mu5);
+	ev2.push_back(mu3); 
+	// notice: all indices are contracted ...
+
+	ex test_cycl = indexed(symbol("A"), sy_cycl(), ev2);
+	test_cycl = test_cycl.simplify_indexed();
+	// ... so there should be zero free indices in the end.
+	return test_cycl.get_free_indices().size();
+}
+
+// Bug in add::eval() could result in numeric terms not being collected into
+// the overall coefficient. Fixed first on Sep 22, 2010 and again on Dec 17 2015
+static unsigned exam_paranoia18()
+{
+	unsigned result = 0;
+
+	ex sqrt2 = sqrt(ex(2));
+	ex e1 = 1 + 2*(sqrt2+1)*(sqrt2-1);
+	if (e1.real_part() != 3) {
+		clog << "real_part(1+2*(sqrt(2)+1)*(sqrt(2)-1)) failed to evaluate to 3\n";
+		++result;
+	}
+
+	ex sqrt3 = sqrt(ex(3));
+	ex e2 = 2 + 2*(sqrt2+1)*(sqrt2-1) - 2*(sqrt3+1)*(sqrt3-1);
+	if (e2.real_part() != 0) {
+		clog << "real_part(2+2*(sqrt(2)+1)*(sqrt(2)-1)-3*(sqrt(3)+1)*(sqrt(3)-1)) failed to evaluate to 0\n";
+		++result;
+	}
+
+	return result;
+}
+
+// Bug in mul::conjugate when factors are evaluated at branch cuts, reported as
+// Sage bug #10964.
+static unsigned exam_paranoia19()
+{
+	symbol a("a");
+	ex e = conjugate(a*sqrt(ex(-2))*sqrt(ex(-3)));
+	ex c = a*conjugate(sqrt(ex(-2)))*conjugate(sqrt(ex(-3)));
+	if (!subs(e-c, a==42).is_zero()) {
+		clog << "subs(a*conjugate(sqrt(-2))*conjugate(sqrt(-3))-conjugate(a*sqrt(-2)*sqrt(-3)),a==42) failed to evaluate to 0\n";
+		return 1;
+	}
+	return 0;
+}
+
+// Bugs in is_polynomial (fixed 2011-05-20 and 2014-07-26).
+static unsigned exam_paranoia20()
+{
+	unsigned result = 0;
+	symbol x("x"), y("y");
+	ex e1 = sqrt(x*x+1)*sqrt(x+1);
+	if (e1.is_polynomial(x)) {
+		clog << "sqrt(x*x+1)*sqrt(x+1) is wrongly reported to be a polynomial in x\n";
+		++result;
+	}
+	ex e2 = sqrt(Pi)*x;
+	if (!e2.is_polynomial(x)) {
+		clog << "sqrt(Pi)*x is wrongly reported to be no polynomial in x\n";
+		++result;
+	}
+	ex e3 = sqrt(x);
+	if (!e3.is_polynomial(y)) {
+		clog << "sqrt(x) is wrongly reported to be no polynomial in y\n";
+		++result;
+	}
+	ex e4 = (1+y)/(2+x);
+	if (e4.is_polynomial(x)) {
+		clog << "(1+y)/(2+x) is wrongly reported to be a polynomial in x\n";
+		++result;
+	}
+	return result;
+}
+
+static unsigned is_polynomial_false_positive()
+{
+	unsigned result = 0;
+	symbol x("x"), n("n");
+	exvector nonpoly_exprs;
+	nonpoly_exprs.push_back(1/(1-x));
+	nonpoly_exprs.push_back(1/(x+1));
+	nonpoly_exprs.push_back(-1/(x-1));
+	nonpoly_exprs.push_back(1/(1-x*x));
+	nonpoly_exprs.push_back(1/(1-pow(x,n)));
+	nonpoly_exprs.push_back(x-1/(x-1));
+	for (exvector::const_iterator ep = nonpoly_exprs.begin();
+	     ep != nonpoly_exprs.end(); ++ep) {
+		if (ep->is_polynomial(x)) {
+			clog << "(" << *ep << ").is_polynomial(" << x << ") "
+			        "erroneously returned true" << endl;
+			++result;
+		}
+	}
+	return result;
+}
+
+// Bug in power::expand reported by Isuru Fernando (fixed 2015-05-07).
+static unsigned exam_paranoia21()
+{
+	symbol x("x");
+	ex e = pow(x + sqrt(ex(2))*x, 2).expand();
+	if (e.nops() != 2) {
+		clog << "(x+sqrt(2)*x)^2 was wrongly expanded to " << e << "\n";
+		return 1;
+	}
+	return 0;
+}
+
+// Bug in power::expand (fixed 2015-07-18).
+static unsigned exam_paranoia22()
+{
+	symbol x("x"), y("y");
+	ex e = pow(sqrt(1+x)+y*sqrt(1+x), 2).expand();
+	if (e.nops() != 6) {
+		clog << "(sqrt(1+x)+y*sqrt(1+x))^2 was wrongly expanded to " << e << "\n";
+		return 1;
+	}
+	return 0;
+}
+
+// Bug in expairseq::evalchildren().
+static unsigned exam_paranoia23()
+{
+	unsigned result = 0;
+	symbol x("x");
+
+	epvector v1;
+	v1.push_back(expair(1, 1));
+	v1.push_back(expair(2*x, -1));
+	ex e1 = add(v1);  // Should be e==1-2*x,
+	if (!e1.is_equal(1-2*x)) {
+		clog << "Failure constructing " << e1 << " from add.\n";
+		++result;
+	}
+
+	epvector v2;
+	v2.push_back(expair(x, 1));
+	v2.push_back(expair(1,-1));
+	ex e2 = mul(v2);  // Should be e==x;
+	if (!e2.is_equal(x)) {
+		clog << "Failure constructing " << e2 << " from mul.\n";
+		++result;
+	}
+
+	return result;
+}
+
+// Bug in sqrfree_yun (fixed 2016-02-02).
+static unsigned exam_paranoia24()
+{
+	unsigned result = 0;
+	symbol x("x");
+	ex e;
+
+	e = (x-1)*(x+1) - x*x + 1;  // an unexpanded 0...
+	try {
+		ex f = sqrfree(e);
+		if (!f.is_zero()) {
+			clog << "sqrfree(" << e << ") returns " << f << " instead of 0\n";
+			++result;
+		}
+	} catch (const exception &err) {
+		clog << "sqrfree(" << e << ") throws " << err.what() << endl;
+		++result;
+	}
+
+	e = pow(x-1,3) - expand(pow(x-1,3));  // ...still after differentiating...
+	try {
+		ex f = sqrfree(e);
+		if (!f.is_zero()) {
+			clog << "sqrfree(" << e << ") returns " << f << " instead of 0\n";
+			++result;
+		}
+	} catch (const exception &err) {
+		clog << "sqrfree(" << e << ") throws " << err.what() << endl;
+		++result;
+	}
+
+	e = pow(x-1,4) - expand(pow(x-1,4));  // ...and after differentiating twice.
+	try {
+		ex f = sqrfree(e);
+		if (!f.is_zero()) {
+			clog << "sqrfree(" << e << ") returns " << f << " instead of 0\n";
+			++result;
+		}
+	} catch (const exception &err) {
+		clog << "sqrfree(" << e << ") throws " << err.what() << endl;
+		++result;
+	}
+
+	return result;
+}
+
+// Bug in add ctor
+unsigned exam_paranoia25()
+{
+	symbol a("a"), b("b"), c("c");
+	ex e = -a + 2*b + c;
+
+	if (e.diff(c).nops() > 1) {
+		clog << "diff(" << e << ",c) was not fully evaluated.\n";
+		return 1;
+	}
+	return 0;
+}
+
+unsigned exam_paranoia()
 {
 	unsigned result = 0;
 	
 	cout << "examining several historic failures just out of paranoia" << flush;
-	clog << "----------several historic failures:" << endl;
 	
 	result += exam_paranoia1();  cout << '.' << flush;
 	result += exam_paranoia2();  cout << '.' << flush;
@@ -392,13 +657,22 @@ unsigned exam_paranoia(void)
 	result += exam_paranoia13();  cout << '.' << flush;
 	result += exam_paranoia14();  cout << '.' << flush;
 	result += exam_paranoia15();  cout << '.' << flush;
-	
-	if (!result) {
-		cout << " passed " << endl;
-		clog << "(no output)" << endl;
-	} else {
-		cout << " failed " << endl;
-	}
+	result += exam_paranoia16();  cout << '.' << flush;
+	result += exam_paranoia17();  cout << '.' << flush;
+	result += exam_paranoia18();  cout << '.' << flush;
+	result += exam_paranoia19();  cout << '.' << flush;
+	result += exam_paranoia20();  cout << '.' << flush;
+	result += is_polynomial_false_positive(); cout << '.' << flush;
+	result += exam_paranoia21();  cout << '.' << flush;
+	result += exam_paranoia22();  cout << '.' << flush;
+	result += exam_paranoia23();  cout << '.' << flush;
+	result += exam_paranoia24();  cout << '.' << flush;
+	result += exam_paranoia25();  cout << '.' << flush;
 	
 	return result;
 }
+
+int main(int argc, char** argv)
+{
+	return exam_paranoia();
+}