Exemplo n.º 1
0
    def test_laggrid3d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test values
        tgt = np.einsum('i,j,k->ijk', y1, y2, y3)
        res = lag.laggrid3d(x1, x2, x3, self.c3d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = lag.laggrid3d(z, z, z, self.c3d)
        assert_(res.shape == (2, 3) * 3)
Exemplo n.º 2
0
    def test_chebgrid2d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test values
        tgt = np.einsum('i,j->ij', y1, y2)
        res = cheb.chebgrid2d(x1, x2, self.c2d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = cheb.chebgrid2d(z, z, self.c2d)
        assert_(res.shape == (2, 3)*2)
Exemplo n.º 3
0
class TestEvaluation(object):
    # coefficients of 1 + 2*x + 3*x**2
    c1d = np.array([9., -14., 6.])
    c2d = np.einsum('i,j->ij', c1d, c1d)
    c3d = np.einsum('i,j,k->ijk', c1d, c1d, c1d)

    # some random values in [-1, 1)
    x = np.random.random((3, 5)) * 2 - 1
    y = polyval(x, [1., 2., 3.])

    def test_lagval(self):
        #check empty input
        assert_equal(lag.lagval([], [1]).size, 0)

        #check normal input)
        x = np.linspace(-1, 1)
        y = [polyval(x, c) for c in Llist]
        for i in range(7):
            msg = "At i=%d" % i
            tgt = y[i]
            res = lag.lagval(x, [0] * i + [1])
            assert_almost_equal(res, tgt, err_msg=msg)

        #check that shape is preserved
        for i in range(3):
            dims = [2] * i
            x = np.zeros(dims)
            assert_equal(lag.lagval(x, [1]).shape, dims)
            assert_equal(lag.lagval(x, [1, 0]).shape, dims)
            assert_equal(lag.lagval(x, [1, 0, 0]).shape, dims)

    def test_lagval2d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test exceptions
        assert_raises(ValueError, lag.lagval2d, x1, x2[:2], self.c2d)

        #test values
        tgt = y1 * y2
        res = lag.lagval2d(x1, x2, self.c2d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = lag.lagval2d(z, z, self.c2d)
        assert_(res.shape == (2, 3))

    def test_lagval3d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test exceptions
        assert_raises(ValueError, lag.lagval3d, x1, x2, x3[:2], self.c3d)

        #test values
        tgt = y1 * y2 * y3
        res = lag.lagval3d(x1, x2, x3, self.c3d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = lag.lagval3d(z, z, z, self.c3d)
        assert_(res.shape == (2, 3))

    def test_laggrid2d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test values
        tgt = np.einsum('i,j->ij', y1, y2)
        res = lag.laggrid2d(x1, x2, self.c2d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = lag.laggrid2d(z, z, self.c2d)
        assert_(res.shape == (2, 3) * 2)

    def test_laggrid3d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test values
        tgt = np.einsum('i,j,k->ijk', y1, y2, y3)
        res = lag.laggrid3d(x1, x2, x3, self.c3d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = lag.laggrid3d(z, z, z, self.c3d)
        assert_(res.shape == (2, 3) * 3)
Exemplo n.º 4
0
class TestEvaluation(object):
    # coefficients of 1 + 2*x + 3*x**2
    c1d = np.array([1., 2., 3.])
    c2d = np.einsum('i,j->ij', c1d, c1d)
    c3d = np.einsum('i,j,k->ijk', c1d, c1d, c1d)

    # some random values in [-1, 1)
    x = np.random.random((3, 5)) * 2 - 1
    y = poly.polyval(x, [1., 2., 3.])

    def test_polyval(self):
        #check empty input
        assert_equal(poly.polyval([], [1]).size, 0)

        #check normal input)
        x = np.linspace(-1, 1)
        y = [x**i for i in range(5)]
        for i in range(5):
            tgt = y[i]
            res = poly.polyval(x, [0] * i + [1])
            assert_almost_equal(res, tgt)
        tgt = x * (x**2 - 1)
        res = poly.polyval(x, [0, -1, 0, 1])
        assert_almost_equal(res, tgt)

        #check that shape is preserved
        for i in range(3):
            dims = [2] * i
            x = np.zeros(dims)
            assert_equal(poly.polyval(x, [1]).shape, dims)
            assert_equal(poly.polyval(x, [1, 0]).shape, dims)
            assert_equal(poly.polyval(x, [1, 0, 0]).shape, dims)

    def test_polyvalfromroots(self):
        # check exception for broadcasting x values over root array with
        # too few dimensions
        assert_raises(ValueError,
                      poly.polyvalfromroots, [1], [1],
                      tensor=False)

        # check empty input
        assert_equal(poly.polyvalfromroots([], [1]).size, 0)
        assert_(poly.polyvalfromroots([], [1]).shape == (0, ))

        # check empty input + multidimensional roots
        assert_equal(poly.polyvalfromroots([], [[1] * 5]).size, 0)
        assert_(poly.polyvalfromroots([], [[1] * 5]).shape == (5, 0))

        # check scalar input
        assert_equal(poly.polyvalfromroots(1, 1), 0)
        assert_(poly.polyvalfromroots(1, np.ones((3, 3))).shape == (3, ))

        # check normal input)
        x = np.linspace(-1, 1)
        y = [x**i for i in range(5)]
        for i in range(1, 5):
            tgt = y[i]
            res = poly.polyvalfromroots(x, [0] * i)
            assert_almost_equal(res, tgt)
        tgt = x * (x - 1) * (x + 1)
        res = poly.polyvalfromroots(x, [-1, 0, 1])
        assert_almost_equal(res, tgt)

        # check that shape is preserved
        for i in range(3):
            dims = [2] * i
            x = np.zeros(dims)
            assert_equal(poly.polyvalfromroots(x, [1]).shape, dims)
            assert_equal(poly.polyvalfromroots(x, [1, 0]).shape, dims)
            assert_equal(poly.polyvalfromroots(x, [1, 0, 0]).shape, dims)

        # check compatibility with factorization
        ptest = [15, 2, -16, -2, 1]
        r = poly.polyroots(ptest)
        x = np.linspace(-1, 1)
        assert_almost_equal(poly.polyval(x, ptest),
                            poly.polyvalfromroots(x, r))

        # check multidimensional arrays of roots and values
        # check tensor=False
        rshape = (3, 5)
        x = np.arange(-3, 2)
        r = np.random.randint(-5, 5, size=rshape)
        res = poly.polyvalfromroots(x, r, tensor=False)
        tgt = np.empty(r.shape[1:])
        for ii in range(tgt.size):
            tgt[ii] = poly.polyvalfromroots(x[ii], r[:, ii])
        assert_equal(res, tgt)

        # check tensor=True
        x = np.vstack([x, 2 * x])
        res = poly.polyvalfromroots(x, r, tensor=True)
        tgt = np.empty(r.shape[1:] + x.shape)
        for ii in range(r.shape[1]):
            for jj in range(x.shape[0]):
                tgt[ii, jj, :] = poly.polyvalfromroots(x[jj], r[:, ii])
        assert_equal(res, tgt)

    def test_polyval2d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test exceptions
        assert_raises(ValueError, poly.polyval2d, x1, x2[:2], self.c2d)

        #test values
        tgt = y1 * y2
        res = poly.polyval2d(x1, x2, self.c2d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = poly.polyval2d(z, z, self.c2d)
        assert_(res.shape == (2, 3))

    def test_polyval3d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test exceptions
        assert_raises(ValueError, poly.polyval3d, x1, x2, x3[:2], self.c3d)

        #test values
        tgt = y1 * y2 * y3
        res = poly.polyval3d(x1, x2, x3, self.c3d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = poly.polyval3d(z, z, z, self.c3d)
        assert_(res.shape == (2, 3))

    def test_polygrid2d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test values
        tgt = np.einsum('i,j->ij', y1, y2)
        res = poly.polygrid2d(x1, x2, self.c2d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = poly.polygrid2d(z, z, self.c2d)
        assert_(res.shape == (2, 3) * 2)

    def test_polygrid3d(self):
        x1, x2, x3 = self.x
        y1, y2, y3 = self.y

        #test values
        tgt = np.einsum('i,j,k->ijk', y1, y2, y3)
        res = poly.polygrid3d(x1, x2, x3, self.c3d)
        assert_almost_equal(res, tgt)

        #test shape
        z = np.ones((2, 3))
        res = poly.polygrid3d(z, z, z, self.c3d)
        assert_(res.shape == (2, 3) * 3)