Exemple #1
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 def test_basis_func(self):
     p = poly.Chebyshev([1, 2, 3])
     assert_equal(self.as_latex(p),
         r'$x \mapsto 1.0\,{T}_{0}(x) + 2.0\,{T}_{1}(x) + 3.0\,{T}_{2}(x)$')
     # affine input - check no surplus parens are added
     p = poly.Chebyshev([1, 2, 3], domain=[-1, 0])
     assert_equal(self.as_latex(p),
         r'$x \mapsto 1.0\,{T}_{0}(1.0 + 2.0x) + 2.0\,{T}_{1}(1.0 + 2.0x) + 3.0\,{T}_{2}(1.0 + 2.0x)$')
Exemple #2
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    def __get_collocation_nodes(self, m, kind):
        """Computes the collocation nodes."""
        # basis coefs
        coefs = np.zeros(m + 1)
        coefs[-1] = 1

        if kind == 'polynomial':
            nodes = polynomial.Polynomial(coefs).roots()

        elif kind == 'chebyshev':
            domain = [self.a, self.b]
            nodes = polynomial.Chebyshev(coefs, domain).roots()

        elif kind == 'legendre':
            domain = [self.a, self.b]
            nodes = polynomial.Legendre(coefs, domain).roots()

        elif kind == 'laguerre':
            domain = [self.a, self.b]
            nodes = polynomial.Laguerre(coefs, domain).roots()

        elif kind == 'hermite':
            domain = [self.a, self.b]
            nodes = polynomial.Hermite(coefs, domain).roots()

        else:
            raise ValueError

        return nodes
def test_set_default_printoptions():
    p = poly.Polynomial([1, 2, 3])
    c = poly.Chebyshev([1, 2, 3])
    poly.set_default_printstyle("ascii")
    assert_equal(str(p), "1.0 + 2.0 x**1 + 3.0 x**2")
    assert_equal(str(c), "1.0 + 2.0 T_1(x) + 3.0 T_2(x)")
    poly.set_default_printstyle("unicode")
    assert_equal(str(p), "1.0 + 2.0·x¹ + 3.0·x²")
    assert_equal(str(c), "1.0 + 2.0·T₁(x) + 3.0·T₂(x)")
    with pytest.raises(ValueError):
        poly.set_default_printstyle("invalid_input")
Exemple #4
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    def __get_cheb_yhat(self, coefs):
        """Constructs a Chebyshev polynomial approximation to the solution."""
        # the solution y is in R^n
        n = coefs.shape[0]

        # create the approximation yhat
        domain = [self.a, self.b]
        yhat = [polynomial.Chebyshev(coefs[i], domain) for i in range(n)]

        # create the approximation of yhat_prime
        yhat_prime = [yhat[i].deriv() for i in range(n)]

        return [yhat, yhat_prime]
Exemple #5
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    def __init__(self, rect, n=11):
        super().__init__()
        self.image = pygame.Surface(rect.size, depth=32)
        self.rect = self.image.get_rect(topleft=rect.topleft)
        self.image.set_colorkey(self.clear)

        p = P.Chebyshev(tycho).linspace(n)

        # scale x terms to rect width
        w2 = self.rect.w / 2
        X = (p[0] * w2) + w2

        # scale y terms to rect height

        Y = abs(p[1] - p[1][0])
        Y *= (self.rect.h - 10) / Y.max()

        # self.points = [self.rect.rect.topleft

        pts = [(int(x), int(y)) for x, y in zip(X, Y)]

        self.pads = [LandingPad(p, 30) for p in pts[1:-1]]

        self.points = [pts[0]]

        for p in self.pads:
            self.points.append(p.rect.bottomleft)
            self.points.append(p.rect.bottomright)

        self.points.extend(
            [pts[-1], self.rect.bottomright, self.rect.bottomleft])

        # relocate the pad to world coordinates
        for pad in self.pads:
            x, y = pad.rect.center
            a, b = self.rect.topleft
            pad.rect.center = a + x, b + y
        self.render()
Exemple #6
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 def test_chebyshev_str(self):
     res = repr(poly.Chebyshev([0, 1]))
     tgt = 'Chebyshev([0., 1.], domain=[-1,  1], window=[-1,  1])'
     assert_equal(res, tgt)
Exemple #7
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 def test_chebyshev_str(self):
     res = str(poly.Chebyshev([0, 1]))
     tgt = 'cheb([0. 1.])'
     assert_equal(res, tgt)
Exemple #8
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 def test_chebyshev_str(self):
     res = repr(poly.Chebyshev([0,1]))
     tgt = 'Chebyshev([0., 1.], [-1., 1.], [-1., 1.])'
     assert_(res, tgt)
Exemple #9
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 def test_chebyshev_str(self):
     res = str(poly.Chebyshev([0,1]))
     tgt = 'leg([0., 1.])'
     assert_(res, tgt)
 def test_chebyshev_str(self, inp, tgt):
     res = str(poly.Chebyshev(inp))
     assert_equal(res, tgt)
Exemple #11
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# In[24]:

p3

# In[25]:

p3.roots()

# In[26]:

p2

# In[27]:

c1 = P.Chebyshev([1, 2, 3])

# In[28]:

c1

# In[29]:

c1.roots()

# In[30]:

c = P.Chebyshev.fromroots([-1, 1])

# In[31]:
Exemple #12
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 def test_chebyshev_str(self):
     res = repr(poly.Chebyshev([0, 1]))
     tgt = ("Chebyshev([0., 1.], domain=[-1,  1], window=[-1,  1], "
            "symbol='x')")
     assert_equal(res, tgt)
# Programa de Franco Benassi
# Proyecto #3 Interfaces Graficas 2020
# Ejercicio 6
import numpy as np
from numpy.linalg import linalg
import numpy.polynomial as P
import matplotlib.pyplot as pt

data = np.load("/home/franco-os/Documentos/Informática/Interfaces de Grafica de Usuario/Proyecto 3/datas/cheby.npy")

x = data[0]
y = data[1]

deg = len(x)-1

A = P.chebyshev.chebvander(x,deg)
c = linalg.solve(A,y)
Resutl = P.Chebyshev(c)
xx = np.linspace(x.min(),x.max(),100)

pt.plot(xx,Resutl(xx),'r',label="Interpolación Chebychev")
pt.scatter(x,y,label="Puntos de datos")
pt.ylabel("F(x)")
pt.xlabel("T(s)")
pt.legend()
pt.show()