Added tick calculation function and unit tests

Author: janakarana

src/app/calc/utilities.cpp

@@ -39,3 +39,35 @@ double utilities::SimpsonsWeight (unsigned int i, unsigned int n)
     if (i % 2 != 0)   return 4.0 / 3.0;
     return 2.0 / 3.0;
 }
+
+double utilities::NiceStep(double range, int initialCircles)
+{
+    double niceStep = 0.0;
+    double roughStep = (initialCircles > 0) ? range / initialCircles : range;
+    double exponent = floor(log10(roughStep));
+    double fraction = roughStep / pow(10, exponent);
+
+    if (fraction < 1.5)
+    {
+        niceStep = 1.0 * pow(10, exponent);
+    }
+    else
+    {
+        if (fraction < 3.0)
+        {
+            niceStep = 2.0 * pow(10, exponent);
+        }
+        else
+        {
+            if (fraction < 7.5)
+            {
+                niceStep = 5.0 * pow(10, exponent);
+            }
+            else
+            {
+                niceStep = 10.0 * pow(10, exponent);
+            }
+        }
+    }
+    return niceStep;
+}

src/app/calc/utilities.h

@@ -15,6 +15,7 @@ class utilities
     double ComplexAbs(std::complex<double> c);
     double ComplexAbsSquared(std::complex<double> c);
     double SimpsonsWeight (unsigned int i, unsigned int n);
+    double NiceStep(double range, int initialCircles);
 };
 
 #endif // UTILITIES_H

src/test/test_utilities.cpp

@@ -89,3 +89,48 @@ void TestUtilities::test_SimpsonsWeight()
     // Even indexed points (2)
     QVERIFY(qFuzzyCompare(mUtilities->SimpsonsWeight(2, n), 2.0/3.0));
 }
+
+//Test case: NiceStep for a small range
+void TestUtilities::test_NiceStep_SmallRange()
+{
+    double range = 1.0;
+    int initialCircles = 10;
+    QCOMPARE(mUtilities->NiceStep(range, initialCircles), 0.1);
+}
+
+//Test case: NiceStep for a large range
+void TestUtilities::test_NiceStep_LargeRange()
+{
+    // Test for fraction < 3.0
+    double range1 = 25.0;
+    int initialCircles1 = 10;
+    QCOMPARE(mUtilities->NiceStep(range1, initialCircles1), 2.0);
+
+    // Test for fraction < 7.5
+    double range2 = 55.0;
+    int initialCircles2 = 10;
+    QCOMPARE(mUtilities->NiceStep(range2, initialCircles2), 5.0);
+
+    // Test for fraction >= 7.5
+    double range3 = 80.0;
+    int initialCircles3 = 10;
+    QCOMPARE(mUtilities->NiceStep(range3, initialCircles3), 10.0);
+}
+
+void TestUtilities::test_NiceStep_EdgeCases()
+{
+    // Range is a power of 10
+    double range1 = 100.0;
+    int initialCircles1 = 10;
+    QCOMPARE(mUtilities->NiceStep(range1, initialCircles1), 10.0);
+
+    // A zero range
+    double range2 = 0.0;
+    int initialCircles2 = 1;
+    QCOMPARE(mUtilities->NiceStep(range2, initialCircles2), 0.0);
+
+    // A zero initialCircle
+    double range3 = 1.0;
+    int initialCircles3 = 0;
+    QCOMPARE(mUtilities->NiceStep(range3, initialCircles3), 1.0);
+}

src/test/test_utilities.h

@@ -20,6 +20,10 @@ private slots:
     void test_ComplexAbsSquared();
     void test_ComplexAbs();
     void test_SimpsonsWeight();
+    void test_NiceStep_SmallRange();
+    void test_NiceStep_LargeRange();
+    void test_NiceStep_EdgeCases();
+
 
 private:
     utilities *mUtilities;