Added simplify and differentiation tests

eo/contrib/mathsym/test/test_diff.cpp

@@ -0,0 +1,17 @@
+#include <Sym.h>
+#include <FunDef.h>
+#include <iostream>
+
+using namespace std;
+
+int main() {
+    
+    Sym v = SymConst(1.2);
+
+    Sym g = exp(-sqr(v));
+
+    cout << g << endl;
+    cout << differentiate(g, v.token()) << endl;
+    
+}
+

eo/contrib/mathsym/test/test_simplify.cpp

@@ -0,0 +1,18 @@
+
+#include <FunDef.h>
+
+using namespace std;
+
+int main() {
+    
+    Sym c1 = SymConst(0.4);
+    Sym c2 = SymConst(0.3);
+    Sym v1 = SymVar(0);
+
+    Sym expr = (c1 + c2) * ( (c1 + c2) * v1);
+    
+    cout << expr << endl;
+    cout << simplify(expr) << endl;
+    
+}
+

eo/contrib/mathsym/test/testeo.cpp

@@ -102,7 +102,7 @@ int main() {
     cout << "****** Evaluation **********" << endl;
     
     Dataset dataset;
-    dataset.load_data("problem4.dat");
+    dataset.load_data("test_data.txt");
     IntervalBoundsCheck check(dataset.input_minima(), dataset.input_maxima());
     ErrorMeasure measure(dataset, 0.90, ErrorMeasure::mean_squared_scaled);