[PATCH 2/3] Make a stronger normalisation for expressions with exponents.

[ginac.git] / check / exam_normalization.cpp

diff --git a/check/exam_normalization.cpp b/check/exam_normalization.cpp
index 27b85db7f0413d950a650e51bb04385b5229767c..c432102193ec2ef5534bc8923b42ebe7f0cb040e 100644 (file)
--- a/check/exam_normalization.cpp
+++ b/check/exam_normalization.cpp
@@ -223,6 +223,38 @@ static unsigned exam_content()
        return result;
 }
 
+static unsigned exam_exponent_law()
+{
+       unsigned result = 0;
+       ex e, d;
+
+       // simple case
+       e = exp(2*x)-1;
+       e /= exp(x)-1;
+       d = exp(x)+1;
+       result += check_normal(e, d);
+
+       // More involved with powers of two exponents
+       e = exp(15*x)+exp(12*x)+2*exp(10*x)+2*exp(7*x);
+       e /= exp(5*x)+exp(2*x);
+       d = pow(exp(5*x), 2) +2*exp(5*x);
+       result += check_normal(e, d);
+
+       lst bases = {
+                5*exp(3*x)+7, // Powers of a single exponent
+                5*exp(3*x)+7*exp(2*x), // Two different factors of a single variable
+                5*exp(3*x)+7*exp(2*y) // Exponent with different variable
+       };
+
+       for (auto den : bases) {
+               e = pow(den, 3).expand();
+               e /= pow(den, 2).expand();
+               result += check_normal(e, den);
+       }
+
+       return result;
+}
+
 unsigned exam_normalization()
 {
        unsigned result = 0;
@@ -234,6 +266,7 @@ unsigned exam_normalization()
        result += exam_normal3(); cout << '.' << flush;
        result += exam_normal4(); cout << '.' << flush;
        result += exam_content(); cout << '.' << flush;
+       result += exam_exponent_law(); cout << '.' << flush;
        
        return result;
 }