public void Absolute()
{
VectorD v = new VectorD(new double[] { -1, -2, -3, -4 });
v.Absolute();
Assert.AreEqual(1, v[0]);
Assert.AreEqual(2, v[1]);
Assert.AreEqual(3, v[2]);
Assert.AreEqual(4, v[3]);
v = new VectorD(new double[] { 1, 2, 3, 4 });
v.Absolute();
Assert.AreEqual(1, v[0]);
Assert.AreEqual(2, v[1]);
Assert.AreEqual(3, v[2]);
Assert.AreEqual(4, v[3]);
}