def jacobi_e2_1d(order, alpha, beta):
"""
jacobi_e2_1d.m - Evaluate the inner product of 1d Jacobi-chaos doubles
Syntax e = jacobi_e2_1d(order, alpha, beta)
Input: order = order of Jacobi-chaos
alpha, beta = parameters of Jacobi-chaos (alpha, beta>-1)
Output: e = 1 x (p+1) row vector containing the result.
NO WARNING MESSAGE IS GIVEN WHEN PARAMETERS ARE OUT OF RANGE.
Original Matlab version by Dongbin Xiu 04/13/2003
"""
e = zeros((order + 1, 1))
np = ceil((2.0 * order + 1.0) / 2.0)
j = jacobi(np, alpha, beta).weights
z = j[:, 0]
w = j[:, 1]
factor = 2 ** (alpha + beta + 1) * gamma(alpha + 1) * gamma(beta + 1) / gamma(alpha + beta + 2)
for i in range(0, order + 1):
e[i] = sum(jacobi(i, alpha, beta)(z) ** 2 * w) / factor
return e
def test_normsOfPolynomials():
"""
make sure the products are computed as expected
"""
mydpp = DPP(20, 2, [[-.5,-.5],[.4,.6]], "test")
print("hey", spi.quad(lambda x: 1/np.sqrt(1-x**2) * sps.jacobi(2,-.5,-.5,monic=1)(x)**2, -1, 1)[0])
expected = spi.quad(lambda x: 1/np.sqrt(1-x**2) * sps.jacobi(2,-.5,-.5,monic=1)(x)**2, -1, 1)[0] * spi.quad(lambda x: (1-x)**.4*(1+x)**.6*sps.jacobi(3,.4,.6,monic=1)(x)**2, -1, 1)[0]
computed = mydpp.squaredNormsOfPolys[(2,3)]
assert round(computed - expected, 5) == 0
def wigner_d(j, mp, m, beta):
"""
Compute the Wigner d-matrix d_{m', m}^j(\beta) using Jacobi polynomials.
Taken from wikipedia which claims Wigner, E.P. 1931 as a source. Matches
the recursion based method in wigner_d_rec.
"""
j = int(j)
mp = int(mp)
m = int(m)
k = min(j + m, j - m, j + mp, j - mp)
if k == j + m:
a = mp - m
l = mp - m
elif k == j - m:
a = m - mp
l = 0
elif k == j + mp:
a = m - mp
l = 0
elif k == j - mp:
a = mp - m
l = mp - m
else:
raise RuntimeError("could not compute a,l")
b = 2 * (j - k) - a
return ((-1.)**l) * (binom(2*j - k, k + a)**0.5) * \
(binom(k+b, b)**-0.5) * (math.sin(0.5*beta)**a) * \
(math.cos(0.5*beta)**b) * jacobi(k,a,b)(math.cos(beta))
def jacobi_d(n, k, a=1, b=1):
"""
kth derivative of Jacobi polynomial.
2016-07-02
"""
from scipy.special import gamma, jacobi
return lambda x: gamma(a + b + n + 1 + k) / 2**k / gamma(
a + b + n + 1) * jacobi(n - k, a + k, b + k)(x)
def poly_to_jacobi(x):
"""x is a poly1d object"""
xc = x.coeffs
N = x.order+1
matrix = zeros(shape=(N,N), dtype=float)
for i in range(N):
matrix[N-i-1:N, i] = jacobi(i,a,b).coeffs
return solve(matrix, xc)
def poly_to_jacobi(x):
"""x is a poly1d object"""
xc = x.coeffs
N = x.order + 1
matrix = zeros(shape=(N, N), dtype=float)
for i in range(N):
matrix[N - i - 1:N, i] = jacobi(i, a, b).coeffs
return solve(matrix, xc)
def get_wignerD_3d(phi_ea, theta_ea, chi_ea, l, m, k):
# Return array of D matrices with L, M, K as l, [-l, l], m
# Calculation based off of below derivation
# https://en.wikipedia.org/wiki/Wigner_D-matrix#Wigner_(small)_d-matrix
m = np.expand_dims(m, 0)
phi_ea = np.expand_dims(phi_ea, axis=-1)
theta_ea = np.expand_dims(theta_ea, axis=-1)
chi_ea = np.expand_dims(chi_ea, axis=-1)
k_array = np.array([l + k, l - k, l, l], dtype=int)
k_matrix = np.tile(np.expand_dims(k_array, -1), m.shape[1])
k_matrix[2, :] += m[0]
k_matrix[3, :] -= m[0]
a_array = np.array([-1 * k, k, k, -1 * k])
a_matrix = np.tile(np.expand_dims(a_array, -1), m.shape[1])
a_matrix += np.array([[1, -1, -1, 1]]).transpose() * m
k_inds = np.argmin(k_matrix, axis=0)
k_, a = np.zeros_like(m), np.zeros_like(m)
ii = np.arange(k_inds.shape[0])
k_[0, :] = k_matrix[k_inds[ii], ii]
a[0, :] = a_matrix[k_inds[ii], ii]
b = 2 * l - 2 * k_ - a
lmbd = (m - k) * np.maximum(0, (1 - (k_inds % 3)))
#lmbd = np.maximum(0, (m - k))
#print(lmbd, (m-k), (1-(k_inds%3)), k_inds)
#print("ll",lmbd)
# Calculate little d
d_coeff = (-1)**lmbd*np.sqrt(nCk_np(2*l-k_, k_+a))/np.sqrt(nCk_np(k_+b, b))\
*np.sin(theta_ea/2)**a*np.cos(theta_ea/2)**b
d = np.zeros_like(d_coeff)
cos_theta = np.cos(theta_ea)
jac = []
for im in range(m.shape[-1]):
p = jacobi(k_[0, im], a[0, im], b[0, im])
jac.append(np.polyval(p, cos_theta)[:, 0])
d[:, im] = d_coeff[:, im] * np.polyval(p, cos_theta)[:, 0]
#print("d", d)
#print("jac", jac)
#print("l", lmbd)
#print("mmmmmmmmmmm", m, np.complex(0,-1))
#print("phi", phi_ea)
#print("res",np.exp(np.complex(0,-1)*m*phi_ea))
# Calculate D matrix element
D_ME = np.exp(np.complex(0, -1) * m * phi_ea) * d * np.exp(
np.complex(0, -1) * k * chi_ea)
#D_ME = d*(np.cos(-1*m*phi_ea) + np.cos(-1*k*chi_ea)\
# + np.complex(0,1)*(np.sin(-1*m*phi_ea) + np.sin(-1*k*chi_ea)))
#print("WTF", np.sin(-1*m*phi_ea))
#print(-1*m*phi_ea)
return D_ME.transpose().astype(np.complex64)
def cone_jacobi(N, n, t):
'''
returns the orthogonal polynomials on the vertical direction
for the cone interior. Here t in [0,1]
'''
jac = ss.jacobi(N - n, 0, 2 + 2 * n)
res = jac(2 * t - 1) * t**n / np.sqrt(8. / (2 * N + 3.))
return res
def jacobi_lobatto(n, a, b):
"""
Weights and collocation points for Gauss-Jacobi-Lobatto quadrature, i.e. Gaussian quadrature using Jacobi polynomials with collocation points as the extrema of the polynomials.
Based on formulas from Huang (
2016-06-30
Params:
-------
n (int)
Collocation points of polynomial of degree n.
a,b (floats)
alpha and beta
Value:
------
coX (ndarray)
Lobatto collocation points.
weights (ndarray)
Weights at collocation points.
"""
assert type(n) is int
assert a > -1 and b > -1
from scipy.special import gamma, gammaln, jacobi, j_roots, factorial
from scipy.special import binom as binomk
pdn = lambda n, a, b, x: (n + a + b + 1) / 2 * jacobi(n - 1, a + 1, b + 1)(
x)
log_g_tilde = lambda a, b, n: (np.log(2) * (
a + b + 1) + gammaln(n + a + 2) + gammaln(n + b + 2) - np.log(
factorial(n + 1)) - gammaln(n + a + b + 2))
an = lambda n: -(a**2 - b**2 + 2 * (a - b)) / ((2 * n + a + b) *
(2 * n + a + b + 2))
bn = lambda n: 4 * (n - 1) * (n + a) * (n + b) * (n + a + b + 1) / (
2 * n + a + b)**2 / (2 * n + a + b + 1) / (2 * n + a + b - 1)
Jn = np.diag([an(i) for i in range(1, n + 1)]) + np.sqrt(
np.diag([bn(i) for i in range(2, n + 1)], k=1) +
np.diag([bn(i) for i in range(2, n + 1)], k=-1))
coX = np.concatenate(([-1], np.sort(np.linalg.eig(Jn)[0]).real, [1]))
weights = np.zeros_like(coX)
n += 1 # In Teng, N+1 is the otal number of points including endpoints.
loggtilde = log_g_tilde(a + 1, b + 1, n - 2)
denom = (1 - coX[1:-1]**2)**2 * (pdn(n - 1, a + 1, b + 1, coX[1:-1]))**2
weights[1:-1] = np.exp(loggtilde) / denom
weights[0] = np.exp(
np.log(2) * (a + b + 1) + np.log(b + 1) + 2 * gammaln(b + 1) +
gammaln(n) + gammaln(n + a + 1) - gammaln(n + b + 1) -
gammaln(n + a + b + 2))
weights[-1] = np.exp(
np.log(2) * (a + b + 1) + np.log(a + 1) + 2 * gammaln(a + 1) +
gammaln(n) + gammaln(n + b + 1) - gammaln(n + a + 1) -
gammaln(n + a + b + 2))
return coX, weights
def wigner_d(s1, s2, theta, l, l_use_bessel=1.e4):
"""
Function to compute the wigner-d matrices
Parameters
----------
s1,s2:
Spin factors for the wigner-d matrix.
theta:
Angular separation for which to compute the wigner-d matrix. The matrix depends on cos(theta).
l:
The spherical harmonics mode ell for which to compute the matrix.
l_use_bessel:
Due to numerical issues, we need to switch from wigner-d matrix to bessel functions at high ell (see the note below).
This defines the scale at which the switch happens.
"""
l0 = np.copy(l)
if l_use_bessel is not None:
#FIXME: This is not great. Due to a issues with the scipy hypergeometric function,
#jacobi can output nan for large ell, l>1.e4
# As a temporary fix, for ell>1.e4, we are replacing the wigner function with the
# bessel function. Fingers and toes crossed!!!
# mpmath is slower and also has convergence issues at large ell.
#https://github.com/scipy/scipy/issues/4446
l = np.atleast_1d(l)
x = l < l_use_bessel
l = np.atleast_1d(l[x])
k = np.amin([l - s1, l - s2, l + s1, l + s2], axis=0)
a = np.absolute(s1 - s2)
lamb = 0 #lambda
if s2 > s1:
lamb = s2 - s1
b = 2 * l - 2 * k - a
d_mat = (-1)**lamb
d_mat *= np.sqrt(
binom(2 * l - k, k + a)
) #this gives array of shape l with elements choose(2l[i]-k[i], k[i]+a)
d_mat /= np.sqrt(binom(k + b, b))
d_mat = np.atleast_1d(d_mat)
x = k < 0
d_mat[x] = 0
d_mat = d_mat.reshape(1, len(d_mat))
theta = theta.reshape(len(theta), 1)
d_mat = d_mat * ((np.sin(theta / 2.0)**a) * (np.cos(theta / 2.0)**b))
d_mat *= jacobi(l, a, b, np.cos(theta))
if l_use_bessel is not None:
l = np.atleast_1d(l0)
x = l >= l_use_bessel
l = np.atleast_1d(l[x])
# d_mat[:,x]=jn(s1-s2,l[x]*theta)
d_mat = np.append(d_mat, jn(s1 - s2, l * theta), axis=1)
return d_mat
def poly_to_jacobi(x):
"""x is a poly1d object representing a function *after dividing by the invariant_distribution*.
This means that:
jacobi_to_poly(poly_to_jacobi(p)) == invariant_distribution * p
up to numerical errors.
"""
xc = x.coeffs
N = x.order + 1
matrix = zeros(shape=(N, N), dtype=float)
for i in range(N):
matrix[N - i - 1:N, i] = jacobi(i, a, b).coeffs
return solve(matrix, xc)
def poly_to_jacobi(x):
"""x is a poly1d object representing a function *after dividing by the invariant_distribution*.
This means that:
jacobi_to_poly(poly_to_jacobi(p)) == invariant_distribution * p
up to numerical errors.
"""
xc = x.coeffs
N = x.order+1
matrix = zeros(shape=(N,N), dtype=float)
for i in range(N):
matrix[N-i-1:N, i] = jacobi(i,a,b).coeffs
return solve(matrix, xc)
def __init__(self, n, m):
k = n - m
if k % 2 == 1:
self.is_zero = True
else:
self.is_zero = False
n_jacobi = k // 2
self.sign = (-1)**n_jacobi
self.m = m
self.n = n
# jacobi form
self.jacobi_pol = jacobi(n=n_jacobi, alpha=m, beta=0)
def normalized_jacobi(n,alpha,beta):
"""
Returns a Jacobi polynomial that is appropriately normalized for
orthonomality under integration with the correct wieght.
Polynomials are a class in python, a powerful one.
Note: not normalized for n = 0. This is to take full advantage of
recurrence relations.
"""
# Our polynomial
poly = jacobi(n,alpha,beta)
# Normalize it
poly /= poly.normcoef
if n == 0:
poly *= np.sqrt(2.0**(-alpha - beta -1)*gamma(alpha+beta+2)/(gamma(alpha+1)*gamma(beta+1)))
return poly
def wigner_d(m1, m2, theta, l, l_use_bessel=1.e4):
"""
Function to compute wigner small-d matrices used in wigner transforms.
"""
l0 = np.copy(l)
if l_use_bessel is not None:
#FIXME: This is not great. Due to a issues with the scipy hypergeometric function,
#jacobi can output nan for large ell, l>1.e4
# As a temporary fix, for ell>1.e4, we are replacing the wigner function with the
# bessel function. Fingers and toes crossed!!!
# mpmath is slower and also has convergence issues at large ell.
#https://github.com/scipy/scipy/issues/4446
l = np.atleast_1d(l)
x = l < l_use_bessel
l = np.atleast_1d(l[x])
k = np.amin([l - m1, l - m2, l + m1, l + m2], axis=0)
a = np.absolute(m1 - m2)
lamb = 0 #lambda
if m2 > m1:
lamb = m2 - m1
b = 2 * l - 2 * k - a
d_mat = (-1)**lamb
d_mat *= np.sqrt(
binom(2 * l - k, k + a)
) #this gives array of shape l with elements choose(2l[i]-k[i], k[i]+a)
d_mat /= np.sqrt(binom(k + b, b))
d_mat = np.atleast_1d(d_mat)
x = k < 0
d_mat[x] = 0
d_mat = d_mat.reshape(1, len(d_mat))
theta = theta.reshape(len(theta), 1)
d_mat = d_mat * ((np.sin(theta / 2.0)**a) * (np.cos(theta / 2.0)**b))
x = d_mat == 0
d_mat *= jacobi(k, a, b, np.cos(theta)) #l
d_mat[x] = 0
if l_use_bessel is not None:
l = np.atleast_1d(l0)
x = l >= l_use_bessel
l = np.atleast_1d(l[x])
# d_mat[:,x]=jn(m1-m2,l[x]*theta)
d_mat = np.append(d_mat, jn(m1 - m2, l * theta), axis=1)
return d_mat
def WignerD( the , l , m , n ) :
"""
Wigner D matrices: d_{mn}^{l}(the)
the -- angle in radians
l -- degree (integer)
m -- order (integer)
n -- order (integer)
"""
if m >= n :
factor = (-1)**(l-m) * np.sqrt( ( scimcm.factorial( l+m ) * scimcm.factorial( l-m ) ) /
( scimcm.factorial( l+n ) * scimcm.factorial( l-n ) ) )
a = m + n
b = m - n
print a
print b
return factor * np.cos( the/2. )**a * ( -np.sin( the/2. ) )**b * scisp.jacobi( l-m , a , b )( -np.cos( the ) )
else :
return (-1)**(m-n) * WignerD( the , l , n , m )
def wignerd(j, m, n=0, approx_lim=100):
'''
Wigner "small d" matrix. (Euler z-y-z convention)
example:
j = 2
m = 1
n = 0
beta = linspace(0,pi,100)
wd210 = wignerd(j,m,n)(beta)
some conditions have to be met:
j >= 0
-j <= m <= j
-j <= n <= j
The approx_lim determines at what point
bessel functions are used. Default is when:
j > m+10
and
j > n+10
for integer l and n=0, we can use the spherical harmonics. If in
addition m=0, we can use the ordinary legendre polynomials.
'''
if (j < 0) or (abs(m) > j) or (abs(n) > j):
raise ValueError("wignerd(j = {0}, m = {1}, n = {2}) value error.".format(j,m,n) \
+ " Valid range for parameters: j>=0, -j<=m,n<=j.")
if (j > (m + approx_lim)) and (j > (n + approx_lim)):
#print 'bessel (approximation)'
return lambda beta: jv(m-n, j*beta)
if (floor(j) == j) and (n == 0):
if m == 0:
#print 'legendre (exact)'
return lambda beta: legendre(j)(np.cos(beta))
elif False:
#print 'spherical harmonics (exact)'
a = np.sqrt(4.*pi / (2.*j + 1.))
return lambda beta: a * np.conjugate(sph_harm(m,j,beta,0.))
jmn_terms = {
j+n : (m-n,m-n),
j-n : (n-m,0.),
j+m : (n-m,0.),
j-m : (m-n,m-n),
}
k = min(jmn_terms)
a, lmb = jmn_terms[k]
b = 2.*j - 2.*k - a
if (a < 0) or (b < 0):
raise ValueError("wignerd(j = {0}, m = {1}, n = {2}) value error.".format(j,m,n) \
+ " Encountered negative values in (a,b) = ({0},{1})".format(a,b))
coeff = np.power(-1.,lmb) * np.sqrt(comb(2.*j-k,k+a)) * (1./np.sqrt(comb(k+b,b)))
#print 'jacobi (exact)'
return lambda beta: coeff\
* np.power(np.sin(0.5*beta),a) \
* np.power(np.cos(0.5*beta),b) \
* jacobi(k,a,b)(np.cos(beta))
def wignerd(j,m,n=0,approx_lim=10):
'''
Wigner "small d" matrix. (Euler z-y-z convention)
example:
j = 2
m = 1
n = 0
beta = linspace(0,pi,100)
wd210 = wignerd(j,m,n)(beta)
some conditions have to be met:
j >= 0
-j <= m <= j
-j <= n <= j
The approx_lim determines at what point
bessel functions are used. Default is when:
j > m+10
and
j > n+10
for integer l and n=0, we can use the spherical harmonics. If in
addition m=0, we can use the ordinary legendre polynomials.
'''
if (j < 0) or (abs(m) > j) or (abs(n) > j):
raise ValueError("wignerd(j = {0}, m = {1}, n = {2}) value error.".format(j,m,n) \
+ " Valid range for parameters: j>=0, -j<=m,n<=j.")
if (j > (m + approx_lim)) and (j > (n + approx_lim)):
#print('bessel (approximation)')
return lambda beta: jv(m-n, j*beta)
if (floor(j) == j) and (n == 0):
if m == 0:
#print('legendre (exact)')
return lambda beta: legendre(j)(cos(beta))
elif False:
#print('spherical harmonics (exact)')
a = sqrt(4.*pi / (2.*j + 1.))
return lambda beta: a * conjugate(sph_harm(m,j,beta,0.))
jmn_terms = {
j+n : (m-n,m-n),
j-n : (n-m,0.),
j+m : (n-m,0.),
j-m : (m-n,m-n),
}
k = min(jmn_terms)
a, lmb = jmn_terms[k]
b = 2.*j - 2.*k - a
if (a < 0) or (b < 0):
raise ValueError("wignerd(j = {0}, m = {1}, n = {2}) value error.".format(j,m,n) \
+ " Encountered negative values in (a,b) = ({0},{1})".format(a,b))
coeff = power(-1.,lmb) * sqrt(comb(2.*j-k,k+a)) * (1./sqrt(comb(k+b,b)))
#print('jacobi (exact)')
return lambda beta: coeff \
* power(sin(0.5*beta),a) \
* power(cos(0.5*beta),b) \
* jacobi(k,a,b)(cos(beta))
def jacobi_to_poly_no_invariant(x):
result = poly1d([0])
for i in range(x.shape[0]):
result = result + jacobi(i,a,b)*x[i]
return result
I0 = I_star[0:1, :]
R0 = R_star[0:1, :]
D0 = D_star[0:1, :]
S0 = N - I0 - R0 - D0
U0 = [S0, I0, R0, D0]
#Residual points
N_f = 500 #5 * len(t_star)
t_f = np.linspace(
lb, ub, num=N_f) #uniformed grid for evaluating fractional derivative
poly_order = 10
t_f_mapped = -1 + 2 / (ub - lb) * (t_f - lb)
t_star_mapped = -1 + 2 / (ub - lb) * (t_star - lb)
Jacobi_polys = np.asarray(
[jacobi(n, 0, 0)(t_f_mapped.flatten()) for n in range(0, 15)])
Jacobi_polys_plots = np.asarray(
[jacobi(n, 0, 0)(t_star_mapped.flatten()) for n in range(0, 15)])
#%%
######################################################################
######################## Training and Predicting ###############################
######################################################################
# t_train = (t_star-lb)/(ub-lb)
t_train = t_star
I_train = I_star
R_train = R_star
D_train = D_star
#%%
from datetime import datetime
def radialfunction_norm(self, n, m, xp, yp):
rho = np.sqrt(xp**2 + yp**2)
omega = abs(m)
sumlimit = (n-omega)//2
return (-1)**sumlimit*rho**omega*jacobi(sumlimit, omega, 0)(
1. - 2.*rho**2)
def jacobi_polynomial(n, a, b, x):
return jacobi(n, a, b)(x)
def jacobi_polynomial_derivative(n, a, b, x, k):
" return derivative of oder k "
ctemp = gamma(a + b + n + 1 + k) / (2**k) / gamma(a + b + n + 1)
return ctemp * jacobi(n - k, a + k, b + k)(x)
def jacobi_to_poly(x):
result = poly1d([0])
for i in range(x.shape[0]):
result = result + (jacobi(i,a,b)*invariant_distribution)*x[i]
return result
def JacobiP_scipy(x,alpha,beta,N):
n = N
return jacobi(n, alpha, beta, monic=0)
def jacobi_to_poly(x):
result = poly1d([0])
for i in range(x.shape[0]):
result = result + (jacobi(i, a, b) * invariant_distribution) * x[i]
return result
def Jacobi(n, a, b, x):
x = np.array(x)
return (jacobi(n, a, b)(x))
def jacobi_to_poly_no_invariant(x):
result = poly1d([0])
for i in range(x.shape[0]):
result = result + jacobi(i, a, b) * x[i]
return result