[PATCH 1/3] Automatic evaluation of (e^t)^s = e^(ts).

[ginac.git] / check / exam_misc.cpp

diff --git a/check/exam_misc.cpp b/check/exam_misc.cpp
index 93b6f8e7d2de414eefb707babcb54b1ef6960c0f..8c28fb5344edcde971182e42616bb75b5f721381 100644 (file)
--- a/check/exam_misc.cpp
+++ b/check/exam_misc.cpp
@@ -255,6 +255,29 @@ static unsigned exam_subs_algebraic()
        return result;
 }
 
+/* Test suitable cases of the exponent power law: (e^t)^s=e^(ts). */
+static unsigned exam_exponent_power_law()
+{
+       unsigned result = 0;
+       symbol x("x");
+       realsymbol s("s");
+       possymbol t("t");
+
+       exmap pwr_exp =
+               { {pow(exp(x), 2), exp(2*x)},
+                 {pow(exp(s), t), exp(s*t)},
+                 {exp(x)*pow(exp(x),-1), 1} };
+
+       for (auto e : pwr_exp) {
+               if (! (e.first.is_equal(e.second)) ) {
+                       clog << "power of exponent  " << e.first << " produces error.\n";
+                       ++result;
+               }
+       }
+
+       return result;
+}
+
 unsigned exam_misc()
 {
        unsigned result = 0;
@@ -268,6 +291,7 @@ unsigned exam_misc()
        result += exam_subs(); cout << '.' << flush;
        result += exam_joris(); cout << '.' << flush;
        result += exam_subs_algebraic(); cout << '.' << flush;
+       result += exam_exponent_power_law(); cout << '.' << flush;
        
        return result;
 }