Fixed database typo and removed unnecessary class identifier.
This commit is contained in:
parent
00ad49a143
commit
45fb349a7d
5098 changed files with 952558 additions and 85 deletions
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59
venv/Lib/site-packages/scipy/special/_precompute/expn_asy.py
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59
venv/Lib/site-packages/scipy/special/_precompute/expn_asy.py
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@ -0,0 +1,59 @@
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"""Precompute the polynomials for the asymptotic expansion of the
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generalized exponential integral.
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Sources
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-------
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[1] NIST, Digital Library of Mathematical Functions,
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https://dlmf.nist.gov/8.20#ii
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"""
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import os
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from numpy.testing import suppress_warnings
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try:
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# Can remove when sympy #11255 is resolved; see
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# https://github.com/sympy/sympy/issues/11255
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with suppress_warnings() as sup:
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sup.filter(DeprecationWarning, "inspect.getargspec.. is deprecated")
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import sympy # type: ignore[import]
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from sympy import Poly
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x = sympy.symbols('x')
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except ImportError:
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pass
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def generate_A(K):
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A = [Poly(1, x)]
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for k in range(K):
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A.append(Poly(1 - 2*k*x, x)*A[k] + Poly(x*(x + 1))*A[k].diff())
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return A
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WARNING = """\
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/* This file was automatically generated by _precompute/expn_asy.py.
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* Do not edit it manually!
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*/
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"""
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def main():
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print(__doc__)
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fn = os.path.join('..', 'cephes', 'expn.h')
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K = 12
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A = generate_A(K)
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with open(fn + '.new', 'w') as f:
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f.write(WARNING)
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f.write("#define nA {}\n".format(len(A)))
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for k, Ak in enumerate(A):
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tmp = ', '.join([str(x.evalf(18)) for x in Ak.coeffs()])
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f.write("static const double A{}[] = {{{}}};\n".format(k, tmp))
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tmp = ", ".join(["A{}".format(k) for k in range(K + 1)])
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f.write("static const double *A[] = {{{}}};\n".format(tmp))
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tmp = ", ".join([str(Ak.degree()) for Ak in A])
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f.write("static const int Adegs[] = {{{}}};\n".format(tmp))
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os.rename(fn + '.new', fn)
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if __name__ == "__main__":
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main()
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115
venv/Lib/site-packages/scipy/special/_precompute/gammainc_asy.py
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115
venv/Lib/site-packages/scipy/special/_precompute/gammainc_asy.py
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@ -0,0 +1,115 @@
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"""
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Precompute coefficients of Temme's asymptotic expansion for gammainc.
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This takes about 8 hours to run on a 2.3 GHz Macbook Pro with 4GB ram.
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Sources:
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[1] NIST, "Digital Library of Mathematical Functions",
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https://dlmf.nist.gov/
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"""
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import os
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from scipy.special._precompute.utils import lagrange_inversion
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try:
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import mpmath as mp # type: ignore[import]
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except ImportError:
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pass
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def compute_a(n):
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"""a_k from DLMF 5.11.6"""
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a = [mp.sqrt(2)/2]
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for k in range(1, n):
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ak = a[-1]/k
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for j in range(1, len(a)):
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ak -= a[j]*a[-j]/(j + 1)
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ak /= a[0]*(1 + mp.mpf(1)/(k + 1))
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a.append(ak)
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return a
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def compute_g(n):
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"""g_k from DLMF 5.11.3/5.11.5"""
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a = compute_a(2*n)
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g = [mp.sqrt(2)*mp.rf(0.5, k)*a[2*k] for k in range(n)]
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return g
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def eta(lam):
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"""Function from DLMF 8.12.1 shifted to be centered at 0."""
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if lam > 0:
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return mp.sqrt(2*(lam - mp.log(lam + 1)))
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elif lam < 0:
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return -mp.sqrt(2*(lam - mp.log(lam + 1)))
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else:
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return 0
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def compute_alpha(n):
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"""alpha_n from DLMF 8.12.13"""
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coeffs = mp.taylor(eta, 0, n - 1)
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return lagrange_inversion(coeffs)
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def compute_d(K, N):
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"""d_{k, n} from DLMF 8.12.12"""
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M = N + 2*K
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d0 = [-mp.mpf(1)/3]
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alpha = compute_alpha(M + 2)
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for n in range(1, M):
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d0.append((n + 2)*alpha[n+2])
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d = [d0]
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g = compute_g(K)
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for k in range(1, K):
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dk = []
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for n in range(M - 2*k):
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dk.append((-1)**k*g[k]*d[0][n] + (n + 2)*d[k-1][n+2])
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d.append(dk)
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for k in range(K):
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d[k] = d[k][:N]
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return d
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header = \
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r"""/* This file was automatically generated by _precomp/gammainc.py.
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* Do not edit it manually!
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*/
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#ifndef IGAM_H
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#define IGAM_H
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#define K {}
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#define N {}
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static const double d[K][N] =
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{{"""
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footer = \
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r"""
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#endif
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"""
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def main():
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print(__doc__)
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K = 25
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N = 25
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with mp.workdps(50):
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d = compute_d(K, N)
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fn = os.path.join(os.path.dirname(__file__), '..', 'cephes', 'igam.h')
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with open(fn + '.new', 'w') as f:
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f.write(header.format(K, N))
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for k, row in enumerate(d):
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row = map(lambda x: mp.nstr(x, 17, min_fixed=0, max_fixed=0), row)
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f.write('{')
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f.write(", ".join(row))
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if k < K - 1:
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f.write('},\n')
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else:
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f.write('}};\n')
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f.write(footer)
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os.rename(fn + '.new', fn)
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if __name__ == "__main__":
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main()
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"""Compute gammainc and gammaincc for large arguments and parameters
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and save the values to data files for use in tests. We can't just
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compare to mpmath's gammainc in test_mpmath.TestSystematic because it
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would take too long.
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Note that mpmath's gammainc is computed using hypercomb, but since it
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doesn't allow the user to increase the maximum number of terms used in
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the series it doesn't converge for many arguments. To get around this
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we copy the mpmath implementation but use more terms.
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This takes about 17 minutes to run on a 2.3 GHz Macbook Pro with 4GB
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ram.
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Sources:
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[1] Fredrik Johansson and others. mpmath: a Python library for
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arbitrary-precision floating-point arithmetic (version 0.19),
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December 2013. http://mpmath.org/.
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"""
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import os
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from time import time
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import numpy as np
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from numpy import pi
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from scipy.special._mptestutils import mpf2float
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try:
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import mpmath as mp # type: ignore[import]
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except ImportError:
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pass
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def gammainc(a, x, dps=50, maxterms=10**8):
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"""Compute gammainc exactly like mpmath does but allow for more
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summands in hypercomb. See
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mpmath/functions/expintegrals.py#L134
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in the mpmath github repository.
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"""
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with mp.workdps(dps):
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z, a, b = mp.mpf(a), mp.mpf(x), mp.mpf(x)
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G = [z]
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negb = mp.fneg(b, exact=True)
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def h(z):
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T1 = [mp.exp(negb), b, z], [1, z, -1], [], G, [1], [1+z], b
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return (T1,)
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res = mp.hypercomb(h, [z], maxterms=maxterms)
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return mpf2float(res)
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def gammaincc(a, x, dps=50, maxterms=10**8):
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"""Compute gammaincc exactly like mpmath does but allow for more
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terms in hypercomb. See
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mpmath/functions/expintegrals.py#L187
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in the mpmath github repository.
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"""
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with mp.workdps(dps):
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z, a = a, x
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if mp.isint(z):
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try:
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# mpmath has a fast integer path
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return mpf2float(mp.gammainc(z, a=a, regularized=True))
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except mp.libmp.NoConvergence:
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pass
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nega = mp.fneg(a, exact=True)
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G = [z]
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# Use 2F0 series when possible; fall back to lower gamma representation
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try:
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def h(z):
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r = z-1
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return [([mp.exp(nega), a], [1, r], [], G, [1, -r], [], 1/nega)]
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return mpf2float(mp.hypercomb(h, [z], force_series=True))
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except mp.libmp.NoConvergence:
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def h(z):
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T1 = [], [1, z-1], [z], G, [], [], 0
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T2 = [-mp.exp(nega), a, z], [1, z, -1], [], G, [1], [1+z], a
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return T1, T2
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return mpf2float(mp.hypercomb(h, [z], maxterms=maxterms))
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def main():
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t0 = time()
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# It would be nice to have data for larger values, but either this
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# requires prohibitively large precision (dps > 800) or mpmath has
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# a bug. For example, gammainc(1e20, 1e20, dps=800) returns a
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# value around 0.03, while the true value should be close to 0.5
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# (DLMF 8.12.15).
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print(__doc__)
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pwd = os.path.dirname(__file__)
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r = np.logspace(4, 14, 30)
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ltheta = np.logspace(np.log10(pi/4), np.log10(np.arctan(0.6)), 30)
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utheta = np.logspace(np.log10(pi/4), np.log10(np.arctan(1.4)), 30)
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regimes = [(gammainc, ltheta), (gammaincc, utheta)]
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for func, theta in regimes:
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rg, thetag = np.meshgrid(r, theta)
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a, x = rg*np.cos(thetag), rg*np.sin(thetag)
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a, x = a.flatten(), x.flatten()
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dataset = []
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for i, (a0, x0) in enumerate(zip(a, x)):
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if func == gammaincc:
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# Exploit the fast integer path in gammaincc whenever
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# possible so that the computation doesn't take too
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# long
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a0, x0 = np.floor(a0), np.floor(x0)
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dataset.append((a0, x0, func(a0, x0)))
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dataset = np.array(dataset)
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filename = os.path.join(pwd, '..', 'tests', 'data', 'local',
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'{}.txt'.format(func.__name__))
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np.savetxt(filename, dataset)
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print("{} minutes elapsed".format((time() - t0)/60))
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if __name__ == "__main__":
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main()
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68
venv/Lib/site-packages/scipy/special/_precompute/lambertw.py
Normal file
68
venv/Lib/site-packages/scipy/special/_precompute/lambertw.py
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"""Compute a Pade approximation for the principle branch of the
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Lambert W function around 0 and compare it to various other
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approximations.
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"""
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import numpy as np
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try:
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import mpmath # type: ignore[import]
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import matplotlib.pyplot as plt # type: ignore[import]
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except ImportError:
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pass
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def lambertw_pade():
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derivs = [mpmath.diff(mpmath.lambertw, 0, n=n) for n in range(6)]
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p, q = mpmath.pade(derivs, 3, 2)
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return p, q
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def main():
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print(__doc__)
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with mpmath.workdps(50):
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p, q = lambertw_pade()
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p, q = p[::-1], q[::-1]
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print("p = {}".format(p))
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print("q = {}".format(q))
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x, y = np.linspace(-1.5, 1.5, 75), np.linspace(-1.5, 1.5, 75)
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x, y = np.meshgrid(x, y)
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z = x + 1j*y
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lambertw_std = []
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for z0 in z.flatten():
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lambertw_std.append(complex(mpmath.lambertw(z0)))
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lambertw_std = np.array(lambertw_std).reshape(x.shape)
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fig, axes = plt.subplots(nrows=3, ncols=1)
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# Compare Pade approximation to true result
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p = np.array([float(p0) for p0 in p])
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q = np.array([float(q0) for q0 in q])
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pade_approx = np.polyval(p, z)/np.polyval(q, z)
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pade_err = abs(pade_approx - lambertw_std)
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axes[0].pcolormesh(x, y, pade_err)
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# Compare two terms of asymptotic series to true result
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asy_approx = np.log(z) - np.log(np.log(z))
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asy_err = abs(asy_approx - lambertw_std)
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axes[1].pcolormesh(x, y, asy_err)
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# Compare two terms of the series around the branch point to the
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# true result
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p = np.sqrt(2*(np.exp(1)*z + 1))
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series_approx = -1 + p - p**2/3
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series_err = abs(series_approx - lambertw_std)
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im = axes[2].pcolormesh(x, y, series_err)
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fig.colorbar(im, ax=axes.ravel().tolist())
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plt.show()
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fig, ax = plt.subplots(nrows=1, ncols=1)
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pade_better = pade_err < asy_err
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im = ax.pcolormesh(x, y, pade_better)
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t = np.linspace(-0.3, 0.3)
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ax.plot(-2.5*abs(t) - 0.2, t, 'r')
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fig.colorbar(im, ax=ax)
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plt.show()
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|
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if __name__ == '__main__':
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main()
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43
venv/Lib/site-packages/scipy/special/_precompute/loggamma.py
Normal file
43
venv/Lib/site-packages/scipy/special/_precompute/loggamma.py
Normal file
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@ -0,0 +1,43 @@
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"""Precompute series coefficients for log-Gamma."""
|
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try:
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import mpmath # type: ignore[import]
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except ImportError:
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pass
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def stirling_series(N):
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with mpmath.workdps(100):
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coeffs = [mpmath.bernoulli(2*n)/(2*n*(2*n - 1))
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for n in range(1, N + 1)]
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return coeffs
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def taylor_series_at_1(N):
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coeffs = []
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with mpmath.workdps(100):
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coeffs.append(-mpmath.euler)
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for n in range(2, N + 1):
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coeffs.append((-1)**n*mpmath.zeta(n)/n)
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return coeffs
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|
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||||
def main():
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print(__doc__)
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print()
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stirling_coeffs = [mpmath.nstr(x, 20, min_fixed=0, max_fixed=0)
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for x in stirling_series(8)[::-1]]
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taylor_coeffs = [mpmath.nstr(x, 20, min_fixed=0, max_fixed=0)
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for x in taylor_series_at_1(23)[::-1]]
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print("Stirling series coefficients")
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print("----------------------------")
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print("\n".join(stirling_coeffs))
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print()
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print("Taylor series coefficients")
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print("--------------------------")
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print("\n".join(taylor_coeffs))
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print()
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||||
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||||
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||||
if __name__ == '__main__':
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main()
|
11
venv/Lib/site-packages/scipy/special/_precompute/setup.py
Normal file
11
venv/Lib/site-packages/scipy/special/_precompute/setup.py
Normal file
|
@ -0,0 +1,11 @@
|
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|
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def configuration(parent_name='special', top_path=None):
|
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from numpy.distutils.misc_util import Configuration
|
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config = Configuration('_precompute', parent_name, top_path)
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return config
|
||||
|
||||
|
||||
if __name__ == '__main__':
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||||
from numpy.distutils.core import setup
|
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setup(**configuration().todict())
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||||
|
|
@ -0,0 +1,120 @@
|
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"""
|
||||
Convergence regions of the expansions used in ``struve.c``
|
||||
|
||||
Note that for v >> z both functions tend rapidly to 0,
|
||||
and for v << -z, they tend to infinity.
|
||||
|
||||
The floating-point functions over/underflow in the lower left and right
|
||||
corners of the figure.
|
||||
|
||||
|
||||
Figure legend
|
||||
=============
|
||||
|
||||
Red region
|
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Power series is close (1e-12) to the mpmath result
|
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|
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Blue region
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Asymptotic series is close to the mpmath result
|
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|
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Green region
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Bessel series is close to the mpmath result
|
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|
||||
Dotted colored lines
|
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Boundaries of the regions
|
||||
|
||||
Solid colored lines
|
||||
Boundaries estimated by the routine itself. These will be used
|
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for determining which of the results to use.
|
||||
|
||||
Black dashed line
|
||||
The line z = 0.7*|v| + 12
|
||||
|
||||
"""
|
||||
import numpy as np
|
||||
import matplotlib.pyplot as plt # type: ignore[import]
|
||||
|
||||
import mpmath # type: ignore[import]
|
||||
|
||||
|
||||
def err_metric(a, b, atol=1e-290):
|
||||
m = abs(a - b) / (atol + abs(b))
|
||||
m[np.isinf(b) & (a == b)] = 0
|
||||
return m
|
||||
|
||||
|
||||
def do_plot(is_h=True):
|
||||
from scipy.special._ufuncs import (_struve_power_series,
|
||||
_struve_asymp_large_z,
|
||||
_struve_bessel_series)
|
||||
|
||||
vs = np.linspace(-1000, 1000, 91)
|
||||
zs = np.sort(np.r_[1e-5, 1.0, np.linspace(0, 700, 91)[1:]])
|
||||
|
||||
rp = _struve_power_series(vs[:,None], zs[None,:], is_h)
|
||||
ra = _struve_asymp_large_z(vs[:,None], zs[None,:], is_h)
|
||||
rb = _struve_bessel_series(vs[:,None], zs[None,:], is_h)
|
||||
|
||||
mpmath.mp.dps = 50
|
||||
if is_h:
|
||||
sh = lambda v, z: float(mpmath.struveh(mpmath.mpf(v), mpmath.mpf(z)))
|
||||
else:
|
||||
sh = lambda v, z: float(mpmath.struvel(mpmath.mpf(v), mpmath.mpf(z)))
|
||||
ex = np.vectorize(sh, otypes='d')(vs[:,None], zs[None,:])
|
||||
|
||||
err_a = err_metric(ra[0], ex) + 1e-300
|
||||
err_p = err_metric(rp[0], ex) + 1e-300
|
||||
err_b = err_metric(rb[0], ex) + 1e-300
|
||||
|
||||
err_est_a = abs(ra[1]/ra[0])
|
||||
err_est_p = abs(rp[1]/rp[0])
|
||||
err_est_b = abs(rb[1]/rb[0])
|
||||
|
||||
z_cutoff = 0.7*abs(vs) + 12
|
||||
|
||||
levels = [-1000, -12]
|
||||
|
||||
plt.cla()
|
||||
|
||||
plt.hold(1)
|
||||
plt.contourf(vs, zs, np.log10(err_p).T, levels=levels, colors=['r', 'r'], alpha=0.1)
|
||||
plt.contourf(vs, zs, np.log10(err_a).T, levels=levels, colors=['b', 'b'], alpha=0.1)
|
||||
plt.contourf(vs, zs, np.log10(err_b).T, levels=levels, colors=['g', 'g'], alpha=0.1)
|
||||
|
||||
plt.contour(vs, zs, np.log10(err_p).T, levels=levels, colors=['r', 'r'], linestyles=[':', ':'])
|
||||
plt.contour(vs, zs, np.log10(err_a).T, levels=levels, colors=['b', 'b'], linestyles=[':', ':'])
|
||||
plt.contour(vs, zs, np.log10(err_b).T, levels=levels, colors=['g', 'g'], linestyles=[':', ':'])
|
||||
|
||||
lp = plt.contour(vs, zs, np.log10(err_est_p).T, levels=levels, colors=['r', 'r'], linestyles=['-', '-'])
|
||||
la = plt.contour(vs, zs, np.log10(err_est_a).T, levels=levels, colors=['b', 'b'], linestyles=['-', '-'])
|
||||
lb = plt.contour(vs, zs, np.log10(err_est_b).T, levels=levels, colors=['g', 'g'], linestyles=['-', '-'])
|
||||
|
||||
plt.clabel(lp, fmt={-1000: 'P', -12: 'P'})
|
||||
plt.clabel(la, fmt={-1000: 'A', -12: 'A'})
|
||||
plt.clabel(lb, fmt={-1000: 'B', -12: 'B'})
|
||||
|
||||
plt.plot(vs, z_cutoff, 'k--')
|
||||
|
||||
plt.xlim(vs.min(), vs.max())
|
||||
plt.ylim(zs.min(), zs.max())
|
||||
|
||||
plt.xlabel('v')
|
||||
plt.ylabel('z')
|
||||
|
||||
|
||||
def main():
|
||||
plt.clf()
|
||||
plt.subplot(121)
|
||||
do_plot(True)
|
||||
plt.title('Struve H')
|
||||
|
||||
plt.subplot(122)
|
||||
do_plot(False)
|
||||
plt.title('Struve L')
|
||||
|
||||
plt.savefig('struve_convergence.png')
|
||||
plt.show()
|
||||
|
||||
|
||||
if __name__ == "__main__":
|
||||
main()
|
44
venv/Lib/site-packages/scipy/special/_precompute/utils.py
Normal file
44
venv/Lib/site-packages/scipy/special/_precompute/utils.py
Normal file
|
@ -0,0 +1,44 @@
|
|||
from numpy.testing import suppress_warnings
|
||||
|
||||
try:
|
||||
import mpmath as mp # type: ignore[import]
|
||||
except ImportError:
|
||||
pass
|
||||
|
||||
try:
|
||||
# Can remove when sympy #11255 is resolved; see
|
||||
# https://github.com/sympy/sympy/issues/11255
|
||||
with suppress_warnings() as sup:
|
||||
sup.filter(DeprecationWarning, "inspect.getargspec.. is deprecated")
|
||||
from sympy.abc import x # type: ignore[import]
|
||||
except ImportError:
|
||||
pass
|
||||
|
||||
|
||||
def lagrange_inversion(a):
|
||||
"""Given a series
|
||||
|
||||
f(x) = a[1]*x + a[2]*x**2 + ... + a[n-1]*x**(n - 1),
|
||||
|
||||
use the Lagrange inversion formula to compute a series
|
||||
|
||||
g(x) = b[1]*x + b[2]*x**2 + ... + b[n-1]*x**(n - 1)
|
||||
|
||||
so that f(g(x)) = g(f(x)) = x mod x**n. We must have a[0] = 0, so
|
||||
necessarily b[0] = 0 too.
|
||||
|
||||
The algorithm is naive and could be improved, but speed isn't an
|
||||
issue here and it's easy to read.
|
||||
|
||||
"""
|
||||
n = len(a)
|
||||
f = sum(a[i]*x**i for i in range(len(a)))
|
||||
h = (x/f).series(x, 0, n).removeO()
|
||||
hpower = [h**0]
|
||||
for k in range(n):
|
||||
hpower.append((hpower[-1]*h).expand())
|
||||
b = [mp.mpf(0)]
|
||||
for k in range(1, n):
|
||||
b.append(hpower[k].coeff(x, k - 1)/k)
|
||||
b = map(lambda x: mp.mpf(x), b)
|
||||
return b
|
|
@ -0,0 +1,41 @@
|
|||
import numpy as np
|
||||
|
||||
try:
|
||||
import mpmath # type: ignore[import]
|
||||
except ImportError:
|
||||
pass
|
||||
|
||||
|
||||
def mpmath_wrightomega(x):
|
||||
return mpmath.lambertw(mpmath.exp(x), mpmath.mpf('-0.5'))
|
||||
|
||||
|
||||
def wrightomega_series_error(x):
|
||||
series = x
|
||||
desired = mpmath_wrightomega(x)
|
||||
return abs(series - desired) / desired
|
||||
|
||||
|
||||
def wrightomega_exp_error(x):
|
||||
exponential_approx = mpmath.exp(x)
|
||||
desired = mpmath_wrightomega(x)
|
||||
return abs(exponential_approx - desired) / desired
|
||||
|
||||
|
||||
def main():
|
||||
desired_error = 2 * np.finfo(float).eps
|
||||
print('Series Error')
|
||||
for x in [1e5, 1e10, 1e15, 1e20]:
|
||||
with mpmath.workdps(100):
|
||||
error = wrightomega_series_error(x)
|
||||
print(x, error, error < desired_error)
|
||||
|
||||
print('Exp error')
|
||||
for x in [-10, -25, -50, -100, -200, -400, -700, -740]:
|
||||
with mpmath.workdps(100):
|
||||
error = wrightomega_exp_error(x)
|
||||
print(x, error, error < desired_error)
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
main()
|
27
venv/Lib/site-packages/scipy/special/_precompute/zetac.py
Normal file
27
venv/Lib/site-packages/scipy/special/_precompute/zetac.py
Normal file
|
@ -0,0 +1,27 @@
|
|||
"""Compute the Taylor series for zeta(x) - 1 around x = 0."""
|
||||
try:
|
||||
import mpmath # type: ignore[import]
|
||||
except ImportError:
|
||||
pass
|
||||
|
||||
|
||||
def zetac_series(N):
|
||||
coeffs = []
|
||||
with mpmath.workdps(100):
|
||||
coeffs.append(-1.5)
|
||||
for n in range(1, N):
|
||||
coeff = mpmath.diff(mpmath.zeta, 0, n)/mpmath.factorial(n)
|
||||
coeffs.append(coeff)
|
||||
return coeffs
|
||||
|
||||
|
||||
def main():
|
||||
print(__doc__)
|
||||
coeffs = zetac_series(10)
|
||||
coeffs = [mpmath.nstr(x, 20, min_fixed=0, max_fixed=0)
|
||||
for x in coeffs]
|
||||
print("\n".join(coeffs[::-1]))
|
||||
|
||||
|
||||
if __name__ == '__main__':
|
||||
main()
|
Loading…
Add table
Add a link
Reference in a new issue