fixed/improved equality/zero checking of Dist

now uses Ginac's numer().is_zero() instead of just is_zero() which is not always clever enough to detect zero-ness

src/CMakeLists.txt

@@ -6,7 +6,7 @@ add_library(${BINARY}_lib STATIC
         Formula.h Formula.cpp
         Dist.h Dist.cpp
         DistributionFactory.h DistributionFactory.cpp
-        Exceptions.h macros.h troolean.h)
+        Exceptions.h macros.h troolean.h troolean.cpp)
 target_link_libraries(${BINARY}_lib PUBLIC ${GINAC_LIBRARIES})
 
 target_link_libraries(${BINARY}_demo PUBLIC ${BINARY}_lib)

src/Dist.cpp

@@ -388,7 +388,9 @@ namespace prodigy {
     }
 
     bool operator==(const Dist &lhs, const Dist &rhs) {
-        return lhs._gf.normal() == rhs._gf.normal();
+        // numer() rewrites to rational expression (a fraction) a returns numerator
+        // otherwise is_zero() does not always yield correct result
+        return (lhs._gf - rhs._gf).numer().is_zero();
     }
 
     Dist operator*(const Dist &lhs, const std::string &rhs) {

src/troolean.cpp

+//
+// Created by Tobias Winkler on 09.11.21.
+//
+
+#include "troolean.h"
+
+namespace prodigy {
+
+    troolean makeTroolean(bool b) {
+        if(b) return troolean::YES;
+        return troolean::NO;
+    }
+
+    std::ostream& operator<<(std::ostream& os, troolean tr) {
+        if(tr == troolean::YES) {
+            return os << "yes";
+        } else if(tr == troolean::NO) {
+            return os << "no";
+        } else {
+            return os << "unknown";
+        }
+    }
+}

src/troolean.h

@@ -5,6 +5,8 @@
 #ifndef PRODIGY_TROOLEAN_H
 #define PRODIGY_TROOLEAN_H
 
+#include <ostream>
+
 namespace prodigy {
 
     enum class troolean {
@@ -13,10 +15,9 @@ namespace prodigy {
         UNKNOWN
     };
 
-    constexpr troolean makeTroolean(bool b) {
-        if(b) return troolean::YES;
-        return troolean::NO;
-    }
+    troolean makeTroolean(bool b);
+
+    std::ostream& operator<<(std::ostream& os, troolean tr);
 
 }
 

test/TestEquivalence.cpp

@@ -85,8 +85,8 @@ TEST(EquivalenceCheck, geometricSum) {
      4: x := 0
      *
      */
-    // l0 = DistributionFactory::geometric("x", "p") * DistributionFactory::geometric("c", "q");
-    l0 = Dist {"1/(1 - p*x)", "p"} * Dist {"1/ (1 - q*c)", "q"};
+    l0 = DistributionFactory::geometric("x", "p") * DistributionFactory::geometric("c", "q");
+    // l0 = Dist {"1/(1 - p*x)", "p"} * Dist {"1/ (1 - q*c)", "q"};
     l1 = l0.updateIid("tmp", DistributionFactory::geometric("TMP", "1/2"), "x");
     l2 = l1.update("c", "c + tmp");
     l3 = l2.update("tmp", "0");
@@ -107,7 +107,8 @@ TEST(EquivalenceCheck, geometricSum) {
      *
      *
      */
-    l0 = Dist {"1/(1 - p*x)", "p"} * Dist {"1/ (1 - q*c)", "q"};
+    l0 = DistributionFactory::geometric("x", "p") * DistributionFactory::geometric("c", "q");
+    // l0 = Dist {"1/(1 - p*x)", "p"} * Dist {"1/ (1 - q*c)", "q"};
     l1 = l0.filterGreater("x", "0");
     l2 = "1/2" * l1.update("x", "x - 1") + "1/2" * l1.update("c", "c + 1");
     l3 = l2.updateIid("tmp", DistributionFactory::geometric("TMP", "1/2"), "x");