public virtual void test_row()
{
double[][] @base = new double[][]
{
new double[] { 1d, 2d },
new double[] { 3d, 4d },
new double[] { 5d, 6d }
};
DoubleMatrix test = DoubleMatrix.copyOf(@base);
assertEquals(test.row(0), DoubleArray.of(1d, 2d));
assertEquals(test.row(1), DoubleArray.of(3d, 4d));
assertEquals(test.row(2), DoubleArray.of(5d, 6d));
assertThrows(() => test.row(-1), typeof(System.IndexOutOfRangeException));
assertThrows(() => test.row(4), typeof(System.IndexOutOfRangeException));
}