--- /dev/null
+package jalview.ext.android;
+
+import static org.testng.Assert.assertEquals;
+
+import org.testng.annotations.Test;
+
+public class SparseDoubleArrayTest
+{
+
+ @Test
+ public void testConstructor()
+ {
+ double[] d = new double[] { 0d, 0d, 1.2d, 0d, 0d, 3.4d };
+ SparseDoubleArray s = new SparseDoubleArray(d);
+ for (int i = 0; i < d.length; i++)
+ {
+ assertEquals(s.get(i), d[i], "At [" + i + "]");
+ }
+ }
+
+ @Test
+ public void testAdd()
+ {
+ double[] d = new double[] { 0d, 0d, 1.2d, 0d, 0d, 3.4d };
+ SparseDoubleArray s = new SparseDoubleArray(d);
+ // add to zero (absent)
+ s.add(0, 3.2d);
+ assertEquals(s.get(0), 3.2d);
+ // add to non-zero
+ s.add(0, 2.5d);
+ assertEquals(s.get(0), 5.7d);
+ // add negative value
+ s.add(2, -5.3d);
+ assertEquals(s.get(2), -4.1d);
+ // add to unset value
+ s.add(12, 9.8d);
+ assertEquals(s.get(12), 9.8d);
+ }
+
+ @Test
+ public void testDivide()
+ {
+ double delta = 1.0e-10;
+ double[] d = new double[] { 0d, 2.4d, 1.2d, 0d, -4.8d, -3.6d };
+ SparseDoubleArray s = new SparseDoubleArray(d);
+ assertEquals(s.divide(0, 1d), 0d); // no such entry
+ assertEquals(s.divide(2, 0d), 0d); // zero divisor
+ assertEquals(s.divide(1, 2d), 1.2d, delta); // + / +
+ assertEquals(s.divide(2, -2d), -0.6d, delta); // + / -
+ assertEquals(s.divide(4, 3d), -1.6d, delta); // - / +
+ assertEquals(s.divide(5, -3d), 1.2d, delta); // - / -
+ }
+}