+
+ /**
+ * Verify that the results of method tred() are the same if the calculation is
+ * redone
+ */
+ @Test(groups = "Functional")
+ public void testTred_reproducible()
+ {
+ /*
+ * make a pseudo-random symmetric matrix as required for tred/tqli
+ */
+ int rows = 10;
+ int cols = rows;
+ double[][] d = getSparseValues(rows, cols, 3);
+
+ /*
+ * make a copy of the values so m1, m2 are not
+ * sharing arrays!
+ */
+ double[][] d1 = new double[rows][cols];
+ for (int row = 0; row < rows; row++)
+ {
+ for (int col = 0; col < cols; col++)
+ {
+ d1[row][col] = d[row][col];
+ }
+ }
+ Matrix m1 = new SparseMatrix(d);
+ Matrix m2 = new SparseMatrix(d1);
+ assertMatricesMatch(m1, m2, 1.0e16); // sanity check
+ m1.tred();
+ m2.tred();
+ assertMatricesMatch(m1, m2, 0.00001d);
+ }