Moved rng-methods to their own class/header

Test/Random__RandomRange.cpp

@@ -0,0 +1,79 @@
+#include "CppUnitTest.h"
+#include "../_TestingUtilities/Testutil.h"
+#include "../Eule/Random.h"
+#include <array>
+#include <sstream>
+
+using namespace Microsoft::VisualStudio::CppUnitTestFramework;
+using namespace Eule;
+
+namespace _Random
+{
+	TEST_CLASS(_RandomRange)
+	{
+	public:
+		
+		// Checks that a random double is never outside the specification, two positive values
+		TEST_METHOD(Random_Doublerange_Never_Outside_Specification__pos__pos)
+		{
+			// Test 1000 random integers
+			for (std::size_t i = 0; i < 1000; i++)
+			{
+				double rnd = Random::RandomRange(49.0, 99.0);
+
+				Assert::IsTrue(rnd >= 49.0, L"rnd too small");
+				Assert::IsTrue(rnd <= 99.0, L"rnd too big");
+			}
+
+			return;
+		}
+
+		// Checks that a random double is never outside the specification, negative minimum
+		TEST_METHOD(Random_Doublerange_Never_Outside_Specification__neg__pos)
+		{
+			// Test 1000 random integers
+			for (std::size_t i = 0; i < 1000; i++)
+			{
+				double rnd = Random::RandomRange(-39.0, 99.0);
+
+				Assert::IsTrue(rnd >= -39.0, L"rnd too small");
+				Assert::IsTrue(rnd <= 99.0, L"rnd too big");
+			}
+
+			return;
+		}
+
+		// Checks that a random double is never outside the specification, two negative values
+		TEST_METHOD(Random_Doublerange_Never_Outside_Specification__neg__neg)
+		{
+			// Test 1000 random integers
+			for (std::size_t i = 0; i < 1000; i++)
+			{
+				double rnd = Random::RandomRange(-39.0, -10.0);
+
+				Assert::IsTrue(rnd >= -39.0, L"rnd too small");
+				Assert::IsTrue(rnd <= -10.0, L"rnd too big");
+			}
+
+			return;
+		}
+
+		// Checks that the produced double-precision floating point distribution shows a big standard deviation
+		TEST_METHOD(Double_Big_Standard_Deviation)
+		{
+			// Setup
+			std::vector<double> rands;
+			rands.resize(100);
+
+			// Exercise
+			// Create 1000 random values
+			std::generate_n(rands.data(), rands.size(), []()->double { return Random::RandomRange(100, 4e9); });
+
+			// Verify
+			const double stddev = Testutil::Stddev(rands);
+			Assert::IsTrue(stddev >= 1000000, (std::wstringstream() << stddev).str().c_str());
+
+			return;
+		}
+	};
+}