public void ShouldExtractVector() { //Arrange var vector = new DenseVector(new[]{1, 2, 3, 4, 5 ,6 ,7.0}); //Act var extracted = vector.Extract(new[] {0, 2, 5}); //Assert AreEqual(3, extracted.Count); AreEqual(new []{1.0, 3.0, 6.0}, extracted.ToArray()); }