Exemple #1
0
    def test_integral(self):
        b = BSpline.basis_element([0, 1, 2])  # x for x < 1 else 2 - x
        assert_allclose(b.integrate(0, 1), 0.5)
        assert_allclose(b.integrate(1, 0), -1 * 0.5)
        assert_allclose(b.integrate(1, 0), -0.5)

        # extrapolate or zeros outside of [0, 2]; default is yes
        assert_allclose(b.integrate(-1, 1), 0)
        assert_allclose(b.integrate(-1, 1, extrapolate=True), 0)
        assert_allclose(b.integrate(-1, 1, extrapolate=False), 0.5)
        assert_allclose(b.integrate(1, -1, extrapolate=False), -1 * 0.5)

        # Test ``_fitpack._splint()``
        t, c, k = b.tck
        assert_allclose(b.integrate(1, -1, extrapolate=False),
                        _splint(t, c, k, 1, -1)[0])

        # Test ``extrapolate='periodic'``.
        b.extrapolate = 'periodic'
        i = b.antiderivative()
        period_int = i(2) - i(0)

        assert_allclose(b.integrate(0, 2), period_int)
        assert_allclose(b.integrate(2, 0), -1 * period_int)
        assert_allclose(b.integrate(-9, -7), period_int)
        assert_allclose(b.integrate(-8, -4), 2 * period_int)

        assert_allclose(b.integrate(0.5, 1.5), i(1.5) - i(0.5))
        assert_allclose(b.integrate(1.5, 3), i(1) - i(0) + i(2) - i(1.5))
        assert_allclose(b.integrate(1.5 + 12, 3 + 12),
                        i(1) - i(0) + i(2) - i(1.5))
        assert_allclose(b.integrate(1.5, 3 + 12),
                        i(1) - i(0) + i(2) - i(1.5) + 6 * period_int)

        assert_allclose(b.integrate(0, -1), i(0) - i(1))
        assert_allclose(b.integrate(-9, -10), i(0) - i(1))
        assert_allclose(b.integrate(0, -9), i(1) - i(2) - 4 * period_int)
    def test_integral(self):
        b = BSpline.basis_element([0, 1, 2])  # x for x < 1 else 2 - x
        assert_allclose(b.integrate(0, 1), 0.5)
        assert_allclose(b.integrate(1, 0), -1 * 0.5)
        assert_allclose(b.integrate(1, 0), -0.5)

        # extrapolate or zeros outside of [0, 2]; default is yes
        assert_allclose(b.integrate(-1, 1), 0)
        assert_allclose(b.integrate(-1, 1, extrapolate=True), 0)
        assert_allclose(b.integrate(-1, 1, extrapolate=False), 0.5)
        assert_allclose(b.integrate(1, -1, extrapolate=False), -1 * 0.5)

        # Test ``_fitpack._splint()``
        t, c, k = b.tck
        assert_allclose(b.integrate(1, -1, extrapolate=False),
                        _splint(t, c, k, 1, -1)[0])

        # Test ``extrapolate='periodic'``.
        b.extrapolate = 'periodic'
        i = b.antiderivative()
        period_int = i(2) - i(0)

        assert_allclose(b.integrate(0, 2), period_int)
        assert_allclose(b.integrate(2, 0), -1 * period_int)
        assert_allclose(b.integrate(-9, -7), period_int)
        assert_allclose(b.integrate(-8, -4), 2 * period_int)

        assert_allclose(b.integrate(0.5, 1.5), i(1.5) - i(0.5))
        assert_allclose(b.integrate(1.5, 3), i(1) - i(0) + i(2) - i(1.5))
        assert_allclose(b.integrate(1.5 + 12, 3 + 12),
                        i(1) - i(0) + i(2) - i(1.5))
        assert_allclose(b.integrate(1.5, 3 + 12),
                        i(1) - i(0) + i(2) - i(1.5) + 6 * period_int)

        assert_allclose(b.integrate(0, -1), i(0) - i(1))
        assert_allclose(b.integrate(-9, -10), i(0) - i(1))
        assert_allclose(b.integrate(0, -9), i(1) - i(2) - 4 * period_int)