3RNN/Lib/site-packages/scipy/special/tests/test_orthogonal.py
2024-05-26 19:49:15 +02:00

805 lines
31 KiB
Python

import numpy as np
from numpy import array, sqrt
from numpy.testing import (assert_array_almost_equal, assert_equal,
assert_almost_equal, assert_allclose)
from pytest import raises as assert_raises
from scipy import integrate
import scipy.special as sc
from scipy.special import gamma
import scipy.special._orthogonal as orth
class TestCheby:
def test_chebyc(self):
C0 = orth.chebyc(0)
C1 = orth.chebyc(1)
with np.errstate(all='ignore'):
C2 = orth.chebyc(2)
C3 = orth.chebyc(3)
C4 = orth.chebyc(4)
C5 = orth.chebyc(5)
assert_array_almost_equal(C0.c,[2],13)
assert_array_almost_equal(C1.c,[1,0],13)
assert_array_almost_equal(C2.c,[1,0,-2],13)
assert_array_almost_equal(C3.c,[1,0,-3,0],13)
assert_array_almost_equal(C4.c,[1,0,-4,0,2],13)
assert_array_almost_equal(C5.c,[1,0,-5,0,5,0],13)
def test_chebys(self):
S0 = orth.chebys(0)
S1 = orth.chebys(1)
S2 = orth.chebys(2)
S3 = orth.chebys(3)
S4 = orth.chebys(4)
S5 = orth.chebys(5)
assert_array_almost_equal(S0.c,[1],13)
assert_array_almost_equal(S1.c,[1,0],13)
assert_array_almost_equal(S2.c,[1,0,-1],13)
assert_array_almost_equal(S3.c,[1,0,-2,0],13)
assert_array_almost_equal(S4.c,[1,0,-3,0,1],13)
assert_array_almost_equal(S5.c,[1,0,-4,0,3,0],13)
def test_chebyt(self):
T0 = orth.chebyt(0)
T1 = orth.chebyt(1)
T2 = orth.chebyt(2)
T3 = orth.chebyt(3)
T4 = orth.chebyt(4)
T5 = orth.chebyt(5)
assert_array_almost_equal(T0.c,[1],13)
assert_array_almost_equal(T1.c,[1,0],13)
assert_array_almost_equal(T2.c,[2,0,-1],13)
assert_array_almost_equal(T3.c,[4,0,-3,0],13)
assert_array_almost_equal(T4.c,[8,0,-8,0,1],13)
assert_array_almost_equal(T5.c,[16,0,-20,0,5,0],13)
def test_chebyu(self):
U0 = orth.chebyu(0)
U1 = orth.chebyu(1)
U2 = orth.chebyu(2)
U3 = orth.chebyu(3)
U4 = orth.chebyu(4)
U5 = orth.chebyu(5)
assert_array_almost_equal(U0.c,[1],13)
assert_array_almost_equal(U1.c,[2,0],13)
assert_array_almost_equal(U2.c,[4,0,-1],13)
assert_array_almost_equal(U3.c,[8,0,-4,0],13)
assert_array_almost_equal(U4.c,[16,0,-12,0,1],13)
assert_array_almost_equal(U5.c,[32,0,-32,0,6,0],13)
class TestGegenbauer:
def test_gegenbauer(self):
a = 5*np.random.random() - 0.5
if np.any(a == 0):
a = -0.2
Ca0 = orth.gegenbauer(0,a)
Ca1 = orth.gegenbauer(1,a)
Ca2 = orth.gegenbauer(2,a)
Ca3 = orth.gegenbauer(3,a)
Ca4 = orth.gegenbauer(4,a)
Ca5 = orth.gegenbauer(5,a)
assert_array_almost_equal(Ca0.c,array([1]),13)
assert_array_almost_equal(Ca1.c,array([2*a,0]),13)
assert_array_almost_equal(Ca2.c,array([2*a*(a+1),0,-a]),13)
assert_array_almost_equal(Ca3.c,array([4*sc.poch(a,3),0,-6*a*(a+1),
0])/3.0,11)
assert_array_almost_equal(Ca4.c,array([4*sc.poch(a,4),0,-12*sc.poch(a,3),
0,3*a*(a+1)])/6.0,11)
assert_array_almost_equal(Ca5.c,array([4*sc.poch(a,5),0,-20*sc.poch(a,4),
0,15*sc.poch(a,3),0])/15.0,11)
class TestHermite:
def test_hermite(self):
H0 = orth.hermite(0)
H1 = orth.hermite(1)
H2 = orth.hermite(2)
H3 = orth.hermite(3)
H4 = orth.hermite(4)
H5 = orth.hermite(5)
assert_array_almost_equal(H0.c,[1],13)
assert_array_almost_equal(H1.c,[2,0],13)
assert_array_almost_equal(H2.c,[4,0,-2],13)
assert_array_almost_equal(H3.c,[8,0,-12,0],13)
assert_array_almost_equal(H4.c,[16,0,-48,0,12],12)
assert_array_almost_equal(H5.c,[32,0,-160,0,120,0],12)
def test_hermitenorm(self):
# He_n(x) = 2**(-n/2) H_n(x/sqrt(2))
psub = np.poly1d([1.0/sqrt(2),0])
H0 = orth.hermitenorm(0)
H1 = orth.hermitenorm(1)
H2 = orth.hermitenorm(2)
H3 = orth.hermitenorm(3)
H4 = orth.hermitenorm(4)
H5 = orth.hermitenorm(5)
he0 = orth.hermite(0)(psub)
he1 = orth.hermite(1)(psub) / sqrt(2)
he2 = orth.hermite(2)(psub) / 2.0
he3 = orth.hermite(3)(psub) / (2*sqrt(2))
he4 = orth.hermite(4)(psub) / 4.0
he5 = orth.hermite(5)(psub) / (4.0*sqrt(2))
assert_array_almost_equal(H0.c,he0.c,13)
assert_array_almost_equal(H1.c,he1.c,13)
assert_array_almost_equal(H2.c,he2.c,13)
assert_array_almost_equal(H3.c,he3.c,13)
assert_array_almost_equal(H4.c,he4.c,13)
assert_array_almost_equal(H5.c,he5.c,13)
class TestShLegendre:
def test_sh_legendre(self):
# P*_n(x) = P_n(2x-1)
psub = np.poly1d([2,-1])
Ps0 = orth.sh_legendre(0)
Ps1 = orth.sh_legendre(1)
Ps2 = orth.sh_legendre(2)
Ps3 = orth.sh_legendre(3)
Ps4 = orth.sh_legendre(4)
Ps5 = orth.sh_legendre(5)
pse0 = orth.legendre(0)(psub)
pse1 = orth.legendre(1)(psub)
pse2 = orth.legendre(2)(psub)
pse3 = orth.legendre(3)(psub)
pse4 = orth.legendre(4)(psub)
pse5 = orth.legendre(5)(psub)
assert_array_almost_equal(Ps0.c,pse0.c,13)
assert_array_almost_equal(Ps1.c,pse1.c,13)
assert_array_almost_equal(Ps2.c,pse2.c,13)
assert_array_almost_equal(Ps3.c,pse3.c,13)
assert_array_almost_equal(Ps4.c,pse4.c,12)
assert_array_almost_equal(Ps5.c,pse5.c,12)
class TestShChebyt:
def test_sh_chebyt(self):
# T*_n(x) = T_n(2x-1)
psub = np.poly1d([2,-1])
Ts0 = orth.sh_chebyt(0)
Ts1 = orth.sh_chebyt(1)
Ts2 = orth.sh_chebyt(2)
Ts3 = orth.sh_chebyt(3)
Ts4 = orth.sh_chebyt(4)
Ts5 = orth.sh_chebyt(5)
tse0 = orth.chebyt(0)(psub)
tse1 = orth.chebyt(1)(psub)
tse2 = orth.chebyt(2)(psub)
tse3 = orth.chebyt(3)(psub)
tse4 = orth.chebyt(4)(psub)
tse5 = orth.chebyt(5)(psub)
assert_array_almost_equal(Ts0.c,tse0.c,13)
assert_array_almost_equal(Ts1.c,tse1.c,13)
assert_array_almost_equal(Ts2.c,tse2.c,13)
assert_array_almost_equal(Ts3.c,tse3.c,13)
assert_array_almost_equal(Ts4.c,tse4.c,12)
assert_array_almost_equal(Ts5.c,tse5.c,12)
class TestShChebyu:
def test_sh_chebyu(self):
# U*_n(x) = U_n(2x-1)
psub = np.poly1d([2,-1])
Us0 = orth.sh_chebyu(0)
Us1 = orth.sh_chebyu(1)
Us2 = orth.sh_chebyu(2)
Us3 = orth.sh_chebyu(3)
Us4 = orth.sh_chebyu(4)
Us5 = orth.sh_chebyu(5)
use0 = orth.chebyu(0)(psub)
use1 = orth.chebyu(1)(psub)
use2 = orth.chebyu(2)(psub)
use3 = orth.chebyu(3)(psub)
use4 = orth.chebyu(4)(psub)
use5 = orth.chebyu(5)(psub)
assert_array_almost_equal(Us0.c,use0.c,13)
assert_array_almost_equal(Us1.c,use1.c,13)
assert_array_almost_equal(Us2.c,use2.c,13)
assert_array_almost_equal(Us3.c,use3.c,13)
assert_array_almost_equal(Us4.c,use4.c,12)
assert_array_almost_equal(Us5.c,use5.c,11)
class TestShJacobi:
def test_sh_jacobi(self):
# G^(p,q)_n(x) = n! gamma(n+p)/gamma(2*n+p) * P^(p-q,q-1)_n(2*x-1)
def conv(n, p):
return gamma(n + 1) * gamma(n + p) / gamma(2 * n + p)
psub = np.poly1d([2,-1])
q = 4 * np.random.random()
p = q-1 + 2*np.random.random()
# print("shifted jacobi p,q = ", p, q)
G0 = orth.sh_jacobi(0,p,q)
G1 = orth.sh_jacobi(1,p,q)
G2 = orth.sh_jacobi(2,p,q)
G3 = orth.sh_jacobi(3,p,q)
G4 = orth.sh_jacobi(4,p,q)
G5 = orth.sh_jacobi(5,p,q)
ge0 = orth.jacobi(0,p-q,q-1)(psub) * conv(0,p)
ge1 = orth.jacobi(1,p-q,q-1)(psub) * conv(1,p)
ge2 = orth.jacobi(2,p-q,q-1)(psub) * conv(2,p)
ge3 = orth.jacobi(3,p-q,q-1)(psub) * conv(3,p)
ge4 = orth.jacobi(4,p-q,q-1)(psub) * conv(4,p)
ge5 = orth.jacobi(5,p-q,q-1)(psub) * conv(5,p)
assert_array_almost_equal(G0.c,ge0.c,13)
assert_array_almost_equal(G1.c,ge1.c,13)
assert_array_almost_equal(G2.c,ge2.c,13)
assert_array_almost_equal(G3.c,ge3.c,13)
assert_array_almost_equal(G4.c,ge4.c,13)
assert_array_almost_equal(G5.c,ge5.c,13)
class TestCall:
def test_call(self):
poly = []
for n in range(5):
poly.extend([x.strip() for x in
("""
orth.jacobi(%(n)d,0.3,0.9)
orth.sh_jacobi(%(n)d,0.3,0.9)
orth.genlaguerre(%(n)d,0.3)
orth.laguerre(%(n)d)
orth.hermite(%(n)d)
orth.hermitenorm(%(n)d)
orth.gegenbauer(%(n)d,0.3)
orth.chebyt(%(n)d)
orth.chebyu(%(n)d)
orth.chebyc(%(n)d)
orth.chebys(%(n)d)
orth.sh_chebyt(%(n)d)
orth.sh_chebyu(%(n)d)
orth.legendre(%(n)d)
orth.sh_legendre(%(n)d)
""" % dict(n=n)).split()
])
with np.errstate(all='ignore'):
for pstr in poly:
p = eval(pstr)
assert_almost_equal(p(0.315), np.poly1d(p.coef)(0.315),
err_msg=pstr)
class TestGenlaguerre:
def test_regression(self):
assert_equal(orth.genlaguerre(1, 1, monic=False)(0), 2.)
assert_equal(orth.genlaguerre(1, 1, monic=True)(0), -2.)
assert_equal(orth.genlaguerre(1, 1, monic=False), np.poly1d([-1, 2]))
assert_equal(orth.genlaguerre(1, 1, monic=True), np.poly1d([1, -2]))
def verify_gauss_quad(root_func, eval_func, weight_func, a, b, N,
rtol=1e-15, atol=5e-14):
# this test is copied from numpy's TestGauss in test_hermite.py
x, w, mu = root_func(N, True)
n = np.arange(N, dtype=np.dtype("long"))
v = eval_func(n[:,np.newaxis], x)
vv = np.dot(v*w, v.T)
vd = 1 / np.sqrt(vv.diagonal())
vv = vd[:, np.newaxis] * vv * vd
assert_allclose(vv, np.eye(N), rtol, atol)
# check that the integral of 1 is correct
assert_allclose(w.sum(), mu, rtol, atol)
# compare the results of integrating a function with quad.
def f(x):
return x ** 3 - 3 * x ** 2 + x - 2
resI = integrate.quad(lambda x: f(x)*weight_func(x), a, b)
resG = np.vdot(f(x), w)
rtol = 1e-6 if 1e-6 < resI[1] else resI[1] * 10
assert_allclose(resI[0], resG, rtol=rtol)
def test_roots_jacobi():
def rf(a, b):
return lambda n, mu: sc.roots_jacobi(n, a, b, mu)
def ef(a, b):
return lambda n, x: sc.eval_jacobi(n, a, b, x)
def wf(a, b):
return lambda x: (1 - x) ** a * (1 + x) ** b
vgq = verify_gauss_quad
vgq(rf(-0.5, -0.75), ef(-0.5, -0.75), wf(-0.5, -0.75), -1., 1., 5)
vgq(rf(-0.5, -0.75), ef(-0.5, -0.75), wf(-0.5, -0.75), -1., 1.,
25, atol=1e-12)
vgq(rf(-0.5, -0.75), ef(-0.5, -0.75), wf(-0.5, -0.75), -1., 1.,
100, atol=1e-11)
vgq(rf(0.5, -0.5), ef(0.5, -0.5), wf(0.5, -0.5), -1., 1., 5)
vgq(rf(0.5, -0.5), ef(0.5, -0.5), wf(0.5, -0.5), -1., 1., 25, atol=1.5e-13)
vgq(rf(0.5, -0.5), ef(0.5, -0.5), wf(0.5, -0.5), -1., 1., 100, atol=2e-12)
vgq(rf(1, 0.5), ef(1, 0.5), wf(1, 0.5), -1., 1., 5, atol=2e-13)
vgq(rf(1, 0.5), ef(1, 0.5), wf(1, 0.5), -1., 1., 25, atol=2e-13)
vgq(rf(1, 0.5), ef(1, 0.5), wf(1, 0.5), -1., 1., 100, atol=1e-12)
vgq(rf(0.9, 2), ef(0.9, 2), wf(0.9, 2), -1., 1., 5)
vgq(rf(0.9, 2), ef(0.9, 2), wf(0.9, 2), -1., 1., 25, atol=1e-13)
vgq(rf(0.9, 2), ef(0.9, 2), wf(0.9, 2), -1., 1., 100, atol=3e-13)
vgq(rf(18.24, 27.3), ef(18.24, 27.3), wf(18.24, 27.3), -1., 1., 5)
vgq(rf(18.24, 27.3), ef(18.24, 27.3), wf(18.24, 27.3), -1., 1., 25,
atol=1.1e-14)
vgq(rf(18.24, 27.3), ef(18.24, 27.3), wf(18.24, 27.3), -1., 1.,
100, atol=1e-13)
vgq(rf(47.1, -0.2), ef(47.1, -0.2), wf(47.1, -0.2), -1., 1., 5, atol=1e-13)
vgq(rf(47.1, -0.2), ef(47.1, -0.2), wf(47.1, -0.2), -1., 1., 25, atol=2e-13)
vgq(rf(47.1, -0.2), ef(47.1, -0.2), wf(47.1, -0.2), -1., 1.,
100, atol=1e-11)
vgq(rf(1., 658.), ef(1., 658.), wf(1., 658.), -1., 1., 5, atol=2e-13)
vgq(rf(1., 658.), ef(1., 658.), wf(1., 658.), -1., 1., 25, atol=1e-12)
vgq(rf(1., 658.), ef(1., 658.), wf(1., 658.), -1., 1., 100, atol=1e-11)
vgq(rf(1., 658.), ef(1., 658.), wf(1., 658.), -1., 1., 250, atol=1e-11)
vgq(rf(511., 511.), ef(511., 511.), wf(511., 511.), -1., 1., 5,
atol=1e-12)
vgq(rf(511., 511.), ef(511., 511.), wf(511., 511.), -1., 1., 25,
atol=1e-11)
vgq(rf(511., 511.), ef(511., 511.), wf(511., 511.), -1., 1., 100,
atol=1e-10)
vgq(rf(511., 512.), ef(511., 512.), wf(511., 512.), -1., 1., 5,
atol=1e-12)
vgq(rf(511., 512.), ef(511., 512.), wf(511., 512.), -1., 1., 25,
atol=1e-11)
vgq(rf(511., 512.), ef(511., 512.), wf(511., 512.), -1., 1., 100,
atol=1e-10)
vgq(rf(1000., 500.), ef(1000., 500.), wf(1000., 500.), -1., 1., 5,
atol=1e-12)
vgq(rf(1000., 500.), ef(1000., 500.), wf(1000., 500.), -1., 1., 25,
atol=1e-11)
vgq(rf(1000., 500.), ef(1000., 500.), wf(1000., 500.), -1., 1., 100,
atol=1e-10)
vgq(rf(2.25, 68.9), ef(2.25, 68.9), wf(2.25, 68.9), -1., 1., 5)
vgq(rf(2.25, 68.9), ef(2.25, 68.9), wf(2.25, 68.9), -1., 1., 25,
atol=1e-13)
vgq(rf(2.25, 68.9), ef(2.25, 68.9), wf(2.25, 68.9), -1., 1., 100,
atol=1e-13)
# when alpha == beta == 0, P_n^{a,b}(x) == P_n(x)
xj, wj = sc.roots_jacobi(6, 0.0, 0.0)
xl, wl = sc.roots_legendre(6)
assert_allclose(xj, xl, 1e-14, 1e-14)
assert_allclose(wj, wl, 1e-14, 1e-14)
# when alpha == beta != 0, P_n^{a,b}(x) == C_n^{alpha+0.5}(x)
xj, wj = sc.roots_jacobi(6, 4.0, 4.0)
xc, wc = sc.roots_gegenbauer(6, 4.5)
assert_allclose(xj, xc, 1e-14, 1e-14)
assert_allclose(wj, wc, 1e-14, 1e-14)
x, w = sc.roots_jacobi(5, 2, 3, False)
y, v, m = sc.roots_jacobi(5, 2, 3, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(wf(2,3), -1, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_jacobi, 0, 1, 1)
assert_raises(ValueError, sc.roots_jacobi, 3.3, 1, 1)
assert_raises(ValueError, sc.roots_jacobi, 3, -2, 1)
assert_raises(ValueError, sc.roots_jacobi, 3, 1, -2)
assert_raises(ValueError, sc.roots_jacobi, 3, -2, -2)
def test_roots_sh_jacobi():
def rf(a, b):
return lambda n, mu: sc.roots_sh_jacobi(n, a, b, mu)
def ef(a, b):
return lambda n, x: sc.eval_sh_jacobi(n, a, b, x)
def wf(a, b):
return lambda x: (1.0 - x) ** (a - b) * x ** (b - 1.0)
vgq = verify_gauss_quad
vgq(rf(-0.5, 0.25), ef(-0.5, 0.25), wf(-0.5, 0.25), 0., 1., 5)
vgq(rf(-0.5, 0.25), ef(-0.5, 0.25), wf(-0.5, 0.25), 0., 1.,
25, atol=1e-12)
vgq(rf(-0.5, 0.25), ef(-0.5, 0.25), wf(-0.5, 0.25), 0., 1.,
100, atol=1e-11)
vgq(rf(0.5, 0.5), ef(0.5, 0.5), wf(0.5, 0.5), 0., 1., 5)
vgq(rf(0.5, 0.5), ef(0.5, 0.5), wf(0.5, 0.5), 0., 1., 25, atol=1e-13)
vgq(rf(0.5, 0.5), ef(0.5, 0.5), wf(0.5, 0.5), 0., 1., 100, atol=1e-12)
vgq(rf(1, 0.5), ef(1, 0.5), wf(1, 0.5), 0., 1., 5)
vgq(rf(1, 0.5), ef(1, 0.5), wf(1, 0.5), 0., 1., 25, atol=1.5e-13)
vgq(rf(1, 0.5), ef(1, 0.5), wf(1, 0.5), 0., 1., 100, atol=2e-12)
vgq(rf(2, 0.9), ef(2, 0.9), wf(2, 0.9), 0., 1., 5)
vgq(rf(2, 0.9), ef(2, 0.9), wf(2, 0.9), 0., 1., 25, atol=1e-13)
vgq(rf(2, 0.9), ef(2, 0.9), wf(2, 0.9), 0., 1., 100, atol=1e-12)
vgq(rf(27.3, 18.24), ef(27.3, 18.24), wf(27.3, 18.24), 0., 1., 5)
vgq(rf(27.3, 18.24), ef(27.3, 18.24), wf(27.3, 18.24), 0., 1., 25)
vgq(rf(27.3, 18.24), ef(27.3, 18.24), wf(27.3, 18.24), 0., 1.,
100, atol=1e-13)
vgq(rf(47.1, 0.2), ef(47.1, 0.2), wf(47.1, 0.2), 0., 1., 5, atol=1e-12)
vgq(rf(47.1, 0.2), ef(47.1, 0.2), wf(47.1, 0.2), 0., 1., 25, atol=1e-11)
vgq(rf(47.1, 0.2), ef(47.1, 0.2), wf(47.1, 0.2), 0., 1., 100, atol=1e-10)
vgq(rf(68.9, 2.25), ef(68.9, 2.25), wf(68.9, 2.25), 0., 1., 5, atol=3.5e-14)
vgq(rf(68.9, 2.25), ef(68.9, 2.25), wf(68.9, 2.25), 0., 1., 25, atol=2e-13)
vgq(rf(68.9, 2.25), ef(68.9, 2.25), wf(68.9, 2.25), 0., 1.,
100, atol=1e-12)
x, w = sc.roots_sh_jacobi(5, 3, 2, False)
y, v, m = sc.roots_sh_jacobi(5, 3, 2, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(wf(3,2), 0, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_sh_jacobi, 0, 1, 1)
assert_raises(ValueError, sc.roots_sh_jacobi, 3.3, 1, 1)
assert_raises(ValueError, sc.roots_sh_jacobi, 3, 1, 2) # p - q <= -1
assert_raises(ValueError, sc.roots_sh_jacobi, 3, 2, -1) # q <= 0
assert_raises(ValueError, sc.roots_sh_jacobi, 3, -2, -1) # both
def test_roots_hermite():
rootf = sc.roots_hermite
evalf = sc.eval_hermite
weightf = orth.hermite(5).weight_func
verify_gauss_quad(rootf, evalf, weightf, -np.inf, np.inf, 5)
verify_gauss_quad(rootf, evalf, weightf, -np.inf, np.inf, 25, atol=1e-13)
verify_gauss_quad(rootf, evalf, weightf, -np.inf, np.inf, 100, atol=1e-12)
# Golub-Welsch branch
x, w = sc.roots_hermite(5, False)
y, v, m = sc.roots_hermite(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -np.inf, np.inf)
assert_allclose(m, muI, rtol=muI_err)
# Asymptotic branch (switch over at n >= 150)
x, w = sc.roots_hermite(200, False)
y, v, m = sc.roots_hermite(200, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
assert_allclose(sum(v), m, 1e-14, 1e-14)
assert_raises(ValueError, sc.roots_hermite, 0)
assert_raises(ValueError, sc.roots_hermite, 3.3)
def test_roots_hermite_asy():
# Recursion for Hermite functions
def hermite_recursion(n, nodes):
H = np.zeros((n, nodes.size))
H[0,:] = np.pi**(-0.25) * np.exp(-0.5*nodes**2)
if n > 1:
H[1,:] = sqrt(2.0) * nodes * H[0,:]
for k in range(2, n):
H[k,:] = sqrt(2.0/k) * nodes * H[k-1,:] - sqrt((k-1.0)/k) * H[k-2,:]
return H
# This tests only the nodes
def test(N, rtol=1e-15, atol=1e-14):
x, w = orth._roots_hermite_asy(N)
H = hermite_recursion(N+1, x)
assert_allclose(H[-1,:], np.zeros(N), rtol, atol)
assert_allclose(sum(w), sqrt(np.pi), rtol, atol)
test(150, atol=1e-12)
test(151, atol=1e-12)
test(300, atol=1e-12)
test(301, atol=1e-12)
test(500, atol=1e-12)
test(501, atol=1e-12)
test(999, atol=1e-12)
test(1000, atol=1e-12)
test(2000, atol=1e-12)
test(5000, atol=1e-12)
def test_roots_hermitenorm():
rootf = sc.roots_hermitenorm
evalf = sc.eval_hermitenorm
weightf = orth.hermitenorm(5).weight_func
verify_gauss_quad(rootf, evalf, weightf, -np.inf, np.inf, 5)
verify_gauss_quad(rootf, evalf, weightf, -np.inf, np.inf, 25, atol=1e-13)
verify_gauss_quad(rootf, evalf, weightf, -np.inf, np.inf, 100, atol=1e-12)
x, w = sc.roots_hermitenorm(5, False)
y, v, m = sc.roots_hermitenorm(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -np.inf, np.inf)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_hermitenorm, 0)
assert_raises(ValueError, sc.roots_hermitenorm, 3.3)
def test_roots_gegenbauer():
def rootf(a):
return lambda n, mu: sc.roots_gegenbauer(n, a, mu)
def evalf(a):
return lambda n, x: sc.eval_gegenbauer(n, a, x)
def weightf(a):
return lambda x: (1 - x ** 2) ** (a - 0.5)
vgq = verify_gauss_quad
vgq(rootf(-0.25), evalf(-0.25), weightf(-0.25), -1., 1., 5)
vgq(rootf(-0.25), evalf(-0.25), weightf(-0.25), -1., 1., 25, atol=1e-12)
vgq(rootf(-0.25), evalf(-0.25), weightf(-0.25), -1., 1., 100, atol=1e-11)
vgq(rootf(0.1), evalf(0.1), weightf(0.1), -1., 1., 5)
vgq(rootf(0.1), evalf(0.1), weightf(0.1), -1., 1., 25, atol=1e-13)
vgq(rootf(0.1), evalf(0.1), weightf(0.1), -1., 1., 100, atol=1e-12)
vgq(rootf(1), evalf(1), weightf(1), -1., 1., 5)
vgq(rootf(1), evalf(1), weightf(1), -1., 1., 25, atol=1e-13)
vgq(rootf(1), evalf(1), weightf(1), -1., 1., 100, atol=1e-12)
vgq(rootf(10), evalf(10), weightf(10), -1., 1., 5)
vgq(rootf(10), evalf(10), weightf(10), -1., 1., 25, atol=1e-13)
vgq(rootf(10), evalf(10), weightf(10), -1., 1., 100, atol=1e-12)
vgq(rootf(50), evalf(50), weightf(50), -1., 1., 5, atol=1e-13)
vgq(rootf(50), evalf(50), weightf(50), -1., 1., 25, atol=1e-12)
vgq(rootf(50), evalf(50), weightf(50), -1., 1., 100, atol=1e-11)
# Alpha=170 is where the approximation used in roots_gegenbauer changes
vgq(rootf(170), evalf(170), weightf(170), -1., 1., 5, atol=1e-13)
vgq(rootf(170), evalf(170), weightf(170), -1., 1., 25, atol=1e-12)
vgq(rootf(170), evalf(170), weightf(170), -1., 1., 100, atol=1e-11)
vgq(rootf(170.5), evalf(170.5), weightf(170.5), -1., 1., 5, atol=1.25e-13)
vgq(rootf(170.5), evalf(170.5), weightf(170.5), -1., 1., 25, atol=1e-12)
vgq(rootf(170.5), evalf(170.5), weightf(170.5), -1., 1., 100, atol=1e-11)
# Test for failures, e.g. overflows, resulting from large alphas
vgq(rootf(238), evalf(238), weightf(238), -1., 1., 5, atol=1e-13)
vgq(rootf(238), evalf(238), weightf(238), -1., 1., 25, atol=1e-12)
vgq(rootf(238), evalf(238), weightf(238), -1., 1., 100, atol=1e-11)
vgq(rootf(512.5), evalf(512.5), weightf(512.5), -1., 1., 5, atol=1e-12)
vgq(rootf(512.5), evalf(512.5), weightf(512.5), -1., 1., 25, atol=1e-11)
vgq(rootf(512.5), evalf(512.5), weightf(512.5), -1., 1., 100, atol=1e-10)
# this is a special case that the old code supported.
# when alpha = 0, the gegenbauer polynomial is uniformly 0. but it goes
# to a scaled down copy of T_n(x) there.
vgq(rootf(0), sc.eval_chebyt, weightf(0), -1., 1., 5)
vgq(rootf(0), sc.eval_chebyt, weightf(0), -1., 1., 25)
vgq(rootf(0), sc.eval_chebyt, weightf(0), -1., 1., 100, atol=1e-12)
x, w = sc.roots_gegenbauer(5, 2, False)
y, v, m = sc.roots_gegenbauer(5, 2, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf(2), -1, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_gegenbauer, 0, 2)
assert_raises(ValueError, sc.roots_gegenbauer, 3.3, 2)
assert_raises(ValueError, sc.roots_gegenbauer, 3, -.75)
def test_roots_chebyt():
weightf = orth.chebyt(5).weight_func
verify_gauss_quad(sc.roots_chebyt, sc.eval_chebyt, weightf, -1., 1., 5)
verify_gauss_quad(sc.roots_chebyt, sc.eval_chebyt, weightf, -1., 1., 25)
verify_gauss_quad(sc.roots_chebyt, sc.eval_chebyt, weightf, -1., 1., 100,
atol=1e-12)
x, w = sc.roots_chebyt(5, False)
y, v, m = sc.roots_chebyt(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -1, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_chebyt, 0)
assert_raises(ValueError, sc.roots_chebyt, 3.3)
def test_chebyt_symmetry():
x, w = sc.roots_chebyt(21)
pos, neg = x[:10], x[11:]
assert_equal(neg, -pos[::-1])
assert_equal(x[10], 0)
def test_roots_chebyu():
weightf = orth.chebyu(5).weight_func
verify_gauss_quad(sc.roots_chebyu, sc.eval_chebyu, weightf, -1., 1., 5)
verify_gauss_quad(sc.roots_chebyu, sc.eval_chebyu, weightf, -1., 1., 25)
verify_gauss_quad(sc.roots_chebyu, sc.eval_chebyu, weightf, -1., 1., 100)
x, w = sc.roots_chebyu(5, False)
y, v, m = sc.roots_chebyu(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -1, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_chebyu, 0)
assert_raises(ValueError, sc.roots_chebyu, 3.3)
def test_roots_chebyc():
weightf = orth.chebyc(5).weight_func
verify_gauss_quad(sc.roots_chebyc, sc.eval_chebyc, weightf, -2., 2., 5)
verify_gauss_quad(sc.roots_chebyc, sc.eval_chebyc, weightf, -2., 2., 25)
verify_gauss_quad(sc.roots_chebyc, sc.eval_chebyc, weightf, -2., 2., 100,
atol=1e-12)
x, w = sc.roots_chebyc(5, False)
y, v, m = sc.roots_chebyc(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -2, 2)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_chebyc, 0)
assert_raises(ValueError, sc.roots_chebyc, 3.3)
def test_roots_chebys():
weightf = orth.chebys(5).weight_func
verify_gauss_quad(sc.roots_chebys, sc.eval_chebys, weightf, -2., 2., 5)
verify_gauss_quad(sc.roots_chebys, sc.eval_chebys, weightf, -2., 2., 25)
verify_gauss_quad(sc.roots_chebys, sc.eval_chebys, weightf, -2., 2., 100)
x, w = sc.roots_chebys(5, False)
y, v, m = sc.roots_chebys(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -2, 2)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_chebys, 0)
assert_raises(ValueError, sc.roots_chebys, 3.3)
def test_roots_sh_chebyt():
weightf = orth.sh_chebyt(5).weight_func
verify_gauss_quad(sc.roots_sh_chebyt, sc.eval_sh_chebyt, weightf, 0., 1., 5)
verify_gauss_quad(sc.roots_sh_chebyt, sc.eval_sh_chebyt, weightf, 0., 1., 25)
verify_gauss_quad(sc.roots_sh_chebyt, sc.eval_sh_chebyt, weightf, 0., 1.,
100, atol=1e-13)
x, w = sc.roots_sh_chebyt(5, False)
y, v, m = sc.roots_sh_chebyt(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, 0, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_sh_chebyt, 0)
assert_raises(ValueError, sc.roots_sh_chebyt, 3.3)
def test_roots_sh_chebyu():
weightf = orth.sh_chebyu(5).weight_func
verify_gauss_quad(sc.roots_sh_chebyu, sc.eval_sh_chebyu, weightf, 0., 1., 5)
verify_gauss_quad(sc.roots_sh_chebyu, sc.eval_sh_chebyu, weightf, 0., 1., 25)
verify_gauss_quad(sc.roots_sh_chebyu, sc.eval_sh_chebyu, weightf, 0., 1.,
100, atol=1e-13)
x, w = sc.roots_sh_chebyu(5, False)
y, v, m = sc.roots_sh_chebyu(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, 0, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_sh_chebyu, 0)
assert_raises(ValueError, sc.roots_sh_chebyu, 3.3)
def test_roots_legendre():
weightf = orth.legendre(5).weight_func
verify_gauss_quad(sc.roots_legendre, sc.eval_legendre, weightf, -1., 1., 5)
verify_gauss_quad(sc.roots_legendre, sc.eval_legendre, weightf, -1., 1.,
25, atol=1e-13)
verify_gauss_quad(sc.roots_legendre, sc.eval_legendre, weightf, -1., 1.,
100, atol=1e-12)
x, w = sc.roots_legendre(5, False)
y, v, m = sc.roots_legendre(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, -1, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_legendre, 0)
assert_raises(ValueError, sc.roots_legendre, 3.3)
def test_roots_sh_legendre():
weightf = orth.sh_legendre(5).weight_func
verify_gauss_quad(sc.roots_sh_legendre, sc.eval_sh_legendre, weightf, 0., 1., 5)
verify_gauss_quad(sc.roots_sh_legendre, sc.eval_sh_legendre, weightf, 0., 1.,
25, atol=1e-13)
verify_gauss_quad(sc.roots_sh_legendre, sc.eval_sh_legendre, weightf, 0., 1.,
100, atol=1e-12)
x, w = sc.roots_sh_legendre(5, False)
y, v, m = sc.roots_sh_legendre(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, 0, 1)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_sh_legendre, 0)
assert_raises(ValueError, sc.roots_sh_legendre, 3.3)
def test_roots_laguerre():
weightf = orth.laguerre(5).weight_func
verify_gauss_quad(sc.roots_laguerre, sc.eval_laguerre, weightf, 0., np.inf, 5)
verify_gauss_quad(sc.roots_laguerre, sc.eval_laguerre, weightf, 0., np.inf,
25, atol=1e-13)
verify_gauss_quad(sc.roots_laguerre, sc.eval_laguerre, weightf, 0., np.inf,
100, atol=1e-12)
x, w = sc.roots_laguerre(5, False)
y, v, m = sc.roots_laguerre(5, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf, 0, np.inf)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_laguerre, 0)
assert_raises(ValueError, sc.roots_laguerre, 3.3)
def test_roots_genlaguerre():
def rootf(a):
return lambda n, mu: sc.roots_genlaguerre(n, a, mu)
def evalf(a):
return lambda n, x: sc.eval_genlaguerre(n, a, x)
def weightf(a):
return lambda x: x ** a * np.exp(-x)
vgq = verify_gauss_quad
vgq(rootf(-0.5), evalf(-0.5), weightf(-0.5), 0., np.inf, 5)
vgq(rootf(-0.5), evalf(-0.5), weightf(-0.5), 0., np.inf, 25, atol=1e-13)
vgq(rootf(-0.5), evalf(-0.5), weightf(-0.5), 0., np.inf, 100, atol=1e-12)
vgq(rootf(0.1), evalf(0.1), weightf(0.1), 0., np.inf, 5)
vgq(rootf(0.1), evalf(0.1), weightf(0.1), 0., np.inf, 25, atol=1e-13)
vgq(rootf(0.1), evalf(0.1), weightf(0.1), 0., np.inf, 100, atol=1.6e-13)
vgq(rootf(1), evalf(1), weightf(1), 0., np.inf, 5)
vgq(rootf(1), evalf(1), weightf(1), 0., np.inf, 25, atol=1e-13)
vgq(rootf(1), evalf(1), weightf(1), 0., np.inf, 100, atol=1.03e-13)
vgq(rootf(10), evalf(10), weightf(10), 0., np.inf, 5)
vgq(rootf(10), evalf(10), weightf(10), 0., np.inf, 25, atol=1e-13)
vgq(rootf(10), evalf(10), weightf(10), 0., np.inf, 100, atol=1e-12)
vgq(rootf(50), evalf(50), weightf(50), 0., np.inf, 5)
vgq(rootf(50), evalf(50), weightf(50), 0., np.inf, 25, atol=1e-13)
vgq(rootf(50), evalf(50), weightf(50), 0., np.inf, 100, rtol=1e-14, atol=2e-13)
x, w = sc.roots_genlaguerre(5, 2, False)
y, v, m = sc.roots_genlaguerre(5, 2, True)
assert_allclose(x, y, 1e-14, 1e-14)
assert_allclose(w, v, 1e-14, 1e-14)
muI, muI_err = integrate.quad(weightf(2.), 0., np.inf)
assert_allclose(m, muI, rtol=muI_err)
assert_raises(ValueError, sc.roots_genlaguerre, 0, 2)
assert_raises(ValueError, sc.roots_genlaguerre, 3.3, 2)
assert_raises(ValueError, sc.roots_genlaguerre, 3, -1.1)
def test_gh_6721():
# Regression test for gh_6721. This should not raise.
sc.chebyt(65)(0.2)