Add more ex::is_polynomial() tests

[ginac.git] / check / exam_paranoia.cpp

diff --git a/check/exam_paranoia.cpp b/check/exam_paranoia.cpp
index 52d261c8b46712962084e373de2de19ae28603c2..d5f65f8e5e644e94319f78349d512f01f5c74b33 100644 (file)
--- a/check/exam_paranoia.cpp
+++ b/check/exam_paranoia.cpp
@@ -494,11 +494,11 @@ static unsigned exam_paranoia19()
        return 0;
 }
 
-// Bug in expairseq::is_polynomial (fixed 2011-05-20).
+// Bugs in is_polynomial (fixed 2011-05-20 and 2014-07-26).
 static unsigned exam_paranoia20()
 {
        unsigned result = 0;
-       symbol x("x");
+       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";
@@ -509,6 +509,38 @@ static unsigned exam_paranoia20()
                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;
 }
 
@@ -538,6 +570,7 @@ unsigned exam_paranoia()
        result += exam_paranoia18();  cout << '.' << flush;
        result += exam_paranoia19();  cout << '.' << flush;
        result += exam_paranoia20();  cout << '.' << flush;
+       result += is_polynomial_false_positive(); cout << '.' << flush;
        
        return result;
 }