671 lines
26 KiB
Python
671 lines
26 KiB
Python
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"""
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Limited tests of the elliptic functions module. A full suite of
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extensive testing can be found in elliptic_torture_tests.py
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Author of the first version: M.T. Taschuk
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References:
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[1] Abramowitz & Stegun. 'Handbook of Mathematical Functions, 9th Ed.',
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(Dover duplicate of 1972 edition)
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[2] Whittaker 'A Course of Modern Analysis, 4th Ed.', 1946,
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Cambridge University Press
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"""
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import mpmath
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import random
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import pytest
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from mpmath import *
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def mpc_ae(a, b, eps=eps):
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res = True
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res = res and a.real.ae(b.real, eps)
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res = res and a.imag.ae(b.imag, eps)
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return res
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zero = mpf(0)
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one = mpf(1)
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jsn = ellipfun('sn')
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jcn = ellipfun('cn')
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jdn = ellipfun('dn')
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calculate_nome = lambda k: qfrom(k=k)
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def test_ellipfun():
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mp.dps = 15
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assert ellipfun('ss', 0, 0) == 1
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assert ellipfun('cc', 0, 0) == 1
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assert ellipfun('dd', 0, 0) == 1
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assert ellipfun('nn', 0, 0) == 1
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assert ellipfun('sn', 0.25, 0).ae(sin(0.25))
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assert ellipfun('cn', 0.25, 0).ae(cos(0.25))
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assert ellipfun('dn', 0.25, 0).ae(1)
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assert ellipfun('ns', 0.25, 0).ae(csc(0.25))
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assert ellipfun('nc', 0.25, 0).ae(sec(0.25))
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assert ellipfun('nd', 0.25, 0).ae(1)
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assert ellipfun('sc', 0.25, 0).ae(tan(0.25))
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assert ellipfun('sd', 0.25, 0).ae(sin(0.25))
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assert ellipfun('cd', 0.25, 0).ae(cos(0.25))
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assert ellipfun('cs', 0.25, 0).ae(cot(0.25))
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assert ellipfun('dc', 0.25, 0).ae(sec(0.25))
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assert ellipfun('ds', 0.25, 0).ae(csc(0.25))
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assert ellipfun('sn', 0.25, 1).ae(tanh(0.25))
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assert ellipfun('cn', 0.25, 1).ae(sech(0.25))
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assert ellipfun('dn', 0.25, 1).ae(sech(0.25))
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assert ellipfun('ns', 0.25, 1).ae(coth(0.25))
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assert ellipfun('nc', 0.25, 1).ae(cosh(0.25))
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assert ellipfun('nd', 0.25, 1).ae(cosh(0.25))
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assert ellipfun('sc', 0.25, 1).ae(sinh(0.25))
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assert ellipfun('sd', 0.25, 1).ae(sinh(0.25))
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assert ellipfun('cd', 0.25, 1).ae(1)
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assert ellipfun('cs', 0.25, 1).ae(csch(0.25))
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assert ellipfun('dc', 0.25, 1).ae(1)
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assert ellipfun('ds', 0.25, 1).ae(csch(0.25))
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assert ellipfun('sn', 0.25, 0.5).ae(0.24615967096986145833)
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assert ellipfun('cn', 0.25, 0.5).ae(0.96922928989378439337)
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assert ellipfun('dn', 0.25, 0.5).ae(0.98473484156599474563)
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assert ellipfun('ns', 0.25, 0.5).ae(4.0624038700573130369)
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assert ellipfun('nc', 0.25, 0.5).ae(1.0317476065024692949)
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assert ellipfun('nd', 0.25, 0.5).ae(1.0155017958029488665)
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assert ellipfun('sc', 0.25, 0.5).ae(0.25397465134058993408)
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assert ellipfun('sd', 0.25, 0.5).ae(0.24997558792415733063)
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assert ellipfun('cd', 0.25, 0.5).ae(0.98425408443195497052)
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assert ellipfun('cs', 0.25, 0.5).ae(3.9374008182374110826)
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assert ellipfun('dc', 0.25, 0.5).ae(1.0159978158253033913)
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assert ellipfun('ds', 0.25, 0.5).ae(4.0003906313579720593)
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def test_calculate_nome():
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mp.dps = 100
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q = calculate_nome(zero)
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assert(q == zero)
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mp.dps = 25
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# used Mathematica's EllipticNomeQ[m]
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math1 = [(mpf(1)/10, mpf('0.006584651553858370274473060')),
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(mpf(2)/10, mpf('0.01394285727531826872146409')),
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(mpf(3)/10, mpf('0.02227743615715350822901627')),
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(mpf(4)/10, mpf('0.03188334731336317755064299')),
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(mpf(5)/10, mpf('0.04321391826377224977441774')),
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(mpf(6)/10, mpf('0.05702025781460967637754953')),
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(mpf(7)/10, mpf('0.07468994353717944761143751')),
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(mpf(8)/10, mpf('0.09927369733882489703607378')),
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(mpf(9)/10, mpf('0.1401731269542615524091055')),
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(mpf(9)/10, mpf('0.1401731269542615524091055'))]
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for i in math1:
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m = i[0]
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q = calculate_nome(sqrt(m))
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assert q.ae(i[1])
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mp.dps = 15
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def test_jtheta():
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mp.dps = 25
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z = q = zero
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for n in range(1,5):
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value = jtheta(n, z, q)
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assert(value == (n-1)//2)
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for q in [one, mpf(2)]:
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for n in range(1,5):
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pytest.raises(ValueError, lambda: jtheta(n, z, q))
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z = one/10
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q = one/11
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# Mathematical N[EllipticTheta[1, 1/10, 1/11], 25]
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res = mpf('0.1069552990104042681962096')
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result = jtheta(1, z, q)
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assert(result.ae(res))
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# Mathematica N[EllipticTheta[2, 1/10, 1/11], 25]
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res = mpf('1.101385760258855791140606')
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result = jtheta(2, z, q)
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assert(result.ae(res))
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# Mathematica N[EllipticTheta[3, 1/10, 1/11], 25]
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res = mpf('1.178319743354331061795905')
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result = jtheta(3, z, q)
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assert(result.ae(res))
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# Mathematica N[EllipticTheta[4, 1/10, 1/11], 25]
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res = mpf('0.8219318954665153577314573')
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result = jtheta(4, z, q)
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assert(result.ae(res))
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# test for sin zeros for jtheta(1, z, q)
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# test for cos zeros for jtheta(2, z, q)
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z1 = pi
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z2 = pi/2
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for i in range(10):
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qstring = str(random.random())
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q = mpf(qstring)
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result = jtheta(1, z1, q)
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assert(result.ae(0))
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result = jtheta(2, z2, q)
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assert(result.ae(0))
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mp.dps = 15
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def test_jtheta_issue_79():
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# near the circle of covergence |q| = 1 the convergence slows
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# down; for |q| > Q_LIM the theta functions raise ValueError
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mp.dps = 30
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mp.dps += 30
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q = mpf(6)/10 - one/10**6 - mpf(8)/10 * j
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mp.dps -= 30
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# Mathematica run first
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# N[EllipticTheta[3, 1, 6/10 - 10^-6 - 8/10*I], 2000]
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# then it works:
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# N[EllipticTheta[3, 1, 6/10 - 10^-6 - 8/10*I], 30]
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res = mpf('32.0031009628901652627099524264') + \
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mpf('16.6153027998236087899308935624') * j
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result = jtheta(3, 1, q)
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# check that for abs(q) > Q_LIM a ValueError exception is raised
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mp.dps += 30
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q = mpf(6)/10 - one/10**7 - mpf(8)/10 * j
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mp.dps -= 30
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pytest.raises(ValueError, lambda: jtheta(3, 1, q))
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# bug reported in issue 79
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mp.dps = 100
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z = (1+j)/3
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q = mpf(368983957219251)/10**15 + mpf(636363636363636)/10**15 * j
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# Mathematica N[EllipticTheta[1, z, q], 35]
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res = mpf('2.4439389177990737589761828991467471') + \
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mpf('0.5446453005688226915290954851851490') *j
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mp.dps = 30
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result = jtheta(1, z, q)
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assert(result.ae(res))
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mp.dps = 80
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z = 3 + 4*j
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q = 0.5 + 0.5*j
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r1 = jtheta(1, z, q)
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mp.dps = 15
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r2 = jtheta(1, z, q)
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assert r1.ae(r2)
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mp.dps = 80
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z = 3 + j
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q1 = exp(j*3)
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# longer test
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# for n in range(1, 6)
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for n in range(1, 2):
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mp.dps = 80
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q = q1*(1 - mpf(1)/10**n)
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r1 = jtheta(1, z, q)
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mp.dps = 15
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r2 = jtheta(1, z, q)
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assert r1.ae(r2)
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mp.dps = 15
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# issue 79 about high derivatives
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assert jtheta(3, 4.5, 0.25, 9).ae(1359.04892680683)
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assert jtheta(3, 4.5, 0.25, 50).ae(-6.14832772630905e+33)
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mp.dps = 50
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r = jtheta(3, 4.5, 0.25, 9)
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assert r.ae('1359.048926806828939547859396600218966947753213803')
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r = jtheta(3, 4.5, 0.25, 50)
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assert r.ae('-6148327726309051673317975084654262.4119215720343656')
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def test_jtheta_identities():
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"""
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Tests the some of the jacobi identidies found in Abramowitz,
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Sec. 16.28, Pg. 576. The identities are tested to 1 part in 10^98.
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"""
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mp.dps = 110
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eps1 = ldexp(eps, 30)
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for i in range(10):
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qstring = str(random.random())
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q = mpf(qstring)
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zstring = str(10*random.random())
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z = mpf(zstring)
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# Abramowitz 16.28.1
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# v_1(z, q)**2 * v_4(0, q)**2 = v_3(z, q)**2 * v_2(0, q)**2
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# - v_2(z, q)**2 * v_3(0, q)**2
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term1 = (jtheta(1, z, q)**2) * (jtheta(4, zero, q)**2)
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term2 = (jtheta(3, z, q)**2) * (jtheta(2, zero, q)**2)
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term3 = (jtheta(2, z, q)**2) * (jtheta(3, zero, q)**2)
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equality = term1 - term2 + term3
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assert(equality.ae(0, eps1))
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zstring = str(100*random.random())
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z = mpf(zstring)
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# Abramowitz 16.28.2
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# v_2(z, q)**2 * v_4(0, q)**2 = v_4(z, q)**2 * v_2(0, q)**2
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# - v_1(z, q)**2 * v_3(0, q)**2
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term1 = (jtheta(2, z, q)**2) * (jtheta(4, zero, q)**2)
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term2 = (jtheta(4, z, q)**2) * (jtheta(2, zero, q)**2)
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term3 = (jtheta(1, z, q)**2) * (jtheta(3, zero, q)**2)
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equality = term1 - term2 + term3
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assert(equality.ae(0, eps1))
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# Abramowitz 16.28.3
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# v_3(z, q)**2 * v_4(0, q)**2 = v_4(z, q)**2 * v_3(0, q)**2
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# - v_1(z, q)**2 * v_2(0, q)**2
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term1 = (jtheta(3, z, q)**2) * (jtheta(4, zero, q)**2)
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term2 = (jtheta(4, z, q)**2) * (jtheta(3, zero, q)**2)
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term3 = (jtheta(1, z, q)**2) * (jtheta(2, zero, q)**2)
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equality = term1 - term2 + term3
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assert(equality.ae(0, eps1))
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# Abramowitz 16.28.4
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# v_4(z, q)**2 * v_4(0, q)**2 = v_3(z, q)**2 * v_3(0, q)**2
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# - v_2(z, q)**2 * v_2(0, q)**2
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term1 = (jtheta(4, z, q)**2) * (jtheta(4, zero, q)**2)
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term2 = (jtheta(3, z, q)**2) * (jtheta(3, zero, q)**2)
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term3 = (jtheta(2, z, q)**2) * (jtheta(2, zero, q)**2)
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equality = term1 - term2 + term3
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assert(equality.ae(0, eps1))
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# Abramowitz 16.28.5
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# v_2(0, q)**4 + v_4(0, q)**4 == v_3(0, q)**4
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term1 = (jtheta(2, zero, q))**4
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term2 = (jtheta(4, zero, q))**4
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term3 = (jtheta(3, zero, q))**4
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equality = term1 + term2 - term3
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assert(equality.ae(0, eps1))
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mp.dps = 15
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def test_jtheta_complex():
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mp.dps = 30
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z = mpf(1)/4 + j/8
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q = mpf(1)/3 + j/7
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# Mathematica N[EllipticTheta[1, 1/4 + I/8, 1/3 + I/7], 35]
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res = mpf('0.31618034835986160705729105731678285') + \
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mpf('0.07542013825835103435142515194358975') * j
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r = jtheta(1, z, q)
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assert(mpc_ae(r, res))
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# Mathematica N[EllipticTheta[2, 1/4 + I/8, 1/3 + I/7], 35]
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res = mpf('1.6530986428239765928634711417951828') + \
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mpf('0.2015344864707197230526742145361455') * j
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r = jtheta(2, z, q)
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assert(mpc_ae(r, res))
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# Mathematica N[EllipticTheta[3, 1/4 + I/8, 1/3 + I/7], 35]
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res = mpf('1.6520564411784228184326012700348340') + \
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mpf('0.1998129119671271328684690067401823') * j
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r = jtheta(3, z, q)
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assert(mpc_ae(r, res))
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# Mathematica N[EllipticTheta[4, 1/4 + I/8, 1/3 + I/7], 35]
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res = mpf('0.37619082382228348252047624089973824') - \
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mpf('0.15623022130983652972686227200681074') * j
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r = jtheta(4, z, q)
|
||
|
|
assert(mpc_ae(r, res))
|
||
|
|
|
||
|
|
# check some theta function identities
|
||
|
|
mp.dos = 100
|
||
|
|
z = mpf(1)/4 + j/8
|
||
|
|
q = mpf(1)/3 + j/7
|
||
|
|
mp.dps += 10
|
||
|
|
a = [0,0, jtheta(2, 0, q), jtheta(3, 0, q), jtheta(4, 0, q)]
|
||
|
|
t = [0, jtheta(1, z, q), jtheta(2, z, q), jtheta(3, z, q), jtheta(4, z, q)]
|
||
|
|
r = [(t[2]*a[4])**2 - (t[4]*a[2])**2 + (t[1] *a[3])**2,
|
||
|
|
(t[3]*a[4])**2 - (t[4]*a[3])**2 + (t[1] *a[2])**2,
|
||
|
|
(t[1]*a[4])**2 - (t[3]*a[2])**2 + (t[2] *a[3])**2,
|
||
|
|
(t[4]*a[4])**2 - (t[3]*a[3])**2 + (t[2] *a[2])**2,
|
||
|
|
a[2]**4 + a[4]**4 - a[3]**4]
|
||
|
|
mp.dps -= 10
|
||
|
|
for x in r:
|
||
|
|
assert(mpc_ae(x, mpc(0)))
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
def test_djtheta():
|
||
|
|
mp.dps = 30
|
||
|
|
|
||
|
|
z = one/7 + j/3
|
||
|
|
q = one/8 + j/5
|
||
|
|
# Mathematica N[EllipticThetaPrime[1, 1/7 + I/3, 1/8 + I/5], 35]
|
||
|
|
res = mpf('1.5555195883277196036090928995803201') - \
|
||
|
|
mpf('0.02439761276895463494054149673076275') * j
|
||
|
|
result = jtheta(1, z, q, 1)
|
||
|
|
assert(mpc_ae(result, res))
|
||
|
|
|
||
|
|
# Mathematica N[EllipticThetaPrime[2, 1/7 + I/3, 1/8 + I/5], 35]
|
||
|
|
res = mpf('0.19825296689470982332701283509685662') - \
|
||
|
|
mpf('0.46038135182282106983251742935250009') * j
|
||
|
|
result = jtheta(2, z, q, 1)
|
||
|
|
assert(mpc_ae(result, res))
|
||
|
|
|
||
|
|
# Mathematica N[EllipticThetaPrime[3, 1/7 + I/3, 1/8 + I/5], 35]
|
||
|
|
res = mpf('0.36492498415476212680896699407390026') - \
|
||
|
|
mpf('0.57743812698666990209897034525640369') * j
|
||
|
|
result = jtheta(3, z, q, 1)
|
||
|
|
assert(mpc_ae(result, res))
|
||
|
|
|
||
|
|
# Mathematica N[EllipticThetaPrime[4, 1/7 + I/3, 1/8 + I/5], 35]
|
||
|
|
res = mpf('-0.38936892528126996010818803742007352') + \
|
||
|
|
mpf('0.66549886179739128256269617407313625') * j
|
||
|
|
result = jtheta(4, z, q, 1)
|
||
|
|
assert(mpc_ae(result, res))
|
||
|
|
|
||
|
|
for i in range(10):
|
||
|
|
q = (one*random.random() + j*random.random())/2
|
||
|
|
# identity in Wittaker, Watson &21.41
|
||
|
|
a = jtheta(1, 0, q, 1)
|
||
|
|
b = jtheta(2, 0, q)*jtheta(3, 0, q)*jtheta(4, 0, q)
|
||
|
|
assert(a.ae(b))
|
||
|
|
|
||
|
|
# test higher derivatives
|
||
|
|
mp.dps = 20
|
||
|
|
for q,z in [(one/3, one/5), (one/3 + j/8, one/5),
|
||
|
|
(one/3, one/5 + j/8), (one/3 + j/7, one/5 + j/8)]:
|
||
|
|
for n in [1, 2, 3, 4]:
|
||
|
|
r = jtheta(n, z, q, 2)
|
||
|
|
r1 = diff(lambda zz: jtheta(n, zz, q), z, n=2)
|
||
|
|
assert r.ae(r1)
|
||
|
|
r = jtheta(n, z, q, 3)
|
||
|
|
r1 = diff(lambda zz: jtheta(n, zz, q), z, n=3)
|
||
|
|
assert r.ae(r1)
|
||
|
|
|
||
|
|
# identity in Wittaker, Watson &21.41
|
||
|
|
q = one/3
|
||
|
|
z = zero
|
||
|
|
a = [0]*5
|
||
|
|
a[1] = jtheta(1, z, q, 3)/jtheta(1, z, q, 1)
|
||
|
|
for n in [2,3,4]:
|
||
|
|
a[n] = jtheta(n, z, q, 2)/jtheta(n, z, q)
|
||
|
|
equality = a[2] + a[3] + a[4] - a[1]
|
||
|
|
assert(equality.ae(0))
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
def test_jsn():
|
||
|
|
"""
|
||
|
|
Test some special cases of the sn(z, q) function.
|
||
|
|
"""
|
||
|
|
mp.dps = 100
|
||
|
|
|
||
|
|
# trival case
|
||
|
|
result = jsn(zero, zero)
|
||
|
|
assert(result == zero)
|
||
|
|
|
||
|
|
# Abramowitz Table 16.5
|
||
|
|
#
|
||
|
|
# sn(0, m) = 0
|
||
|
|
|
||
|
|
for i in range(10):
|
||
|
|
qstring = str(random.random())
|
||
|
|
q = mpf(qstring)
|
||
|
|
|
||
|
|
equality = jsn(zero, q)
|
||
|
|
assert(equality.ae(0))
|
||
|
|
|
||
|
|
# Abramowitz Table 16.6.1
|
||
|
|
#
|
||
|
|
# sn(z, 0) = sin(z), m == 0
|
||
|
|
#
|
||
|
|
# sn(z, 1) = tanh(z), m == 1
|
||
|
|
#
|
||
|
|
# It would be nice to test these, but I find that they run
|
||
|
|
# in to numerical trouble. I'm currently treating as a boundary
|
||
|
|
# case for sn function.
|
||
|
|
|
||
|
|
mp.dps = 25
|
||
|
|
arg = one/10
|
||
|
|
#N[JacobiSN[1/10, 2^-100], 25]
|
||
|
|
res = mpf('0.09983341664682815230681420')
|
||
|
|
m = ldexp(one, -100)
|
||
|
|
result = jsn(arg, m)
|
||
|
|
assert(result.ae(res))
|
||
|
|
|
||
|
|
# N[JacobiSN[1/10, 1/10], 25]
|
||
|
|
res = mpf('0.09981686718599080096451168')
|
||
|
|
result = jsn(arg, arg)
|
||
|
|
assert(result.ae(res))
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
def test_jcn():
|
||
|
|
"""
|
||
|
|
Test some special cases of the cn(z, q) function.
|
||
|
|
"""
|
||
|
|
mp.dps = 100
|
||
|
|
|
||
|
|
# Abramowitz Table 16.5
|
||
|
|
# cn(0, q) = 1
|
||
|
|
qstring = str(random.random())
|
||
|
|
q = mpf(qstring)
|
||
|
|
cn = jcn(zero, q)
|
||
|
|
assert(cn.ae(one))
|
||
|
|
|
||
|
|
# Abramowitz Table 16.6.2
|
||
|
|
#
|
||
|
|
# cn(u, 0) = cos(u), m == 0
|
||
|
|
#
|
||
|
|
# cn(u, 1) = sech(z), m == 1
|
||
|
|
#
|
||
|
|
# It would be nice to test these, but I find that they run
|
||
|
|
# in to numerical trouble. I'm currently treating as a boundary
|
||
|
|
# case for cn function.
|
||
|
|
|
||
|
|
mp.dps = 25
|
||
|
|
arg = one/10
|
||
|
|
m = ldexp(one, -100)
|
||
|
|
#N[JacobiCN[1/10, 2^-100], 25]
|
||
|
|
res = mpf('0.9950041652780257660955620')
|
||
|
|
result = jcn(arg, m)
|
||
|
|
assert(result.ae(res))
|
||
|
|
|
||
|
|
# N[JacobiCN[1/10, 1/10], 25]
|
||
|
|
res = mpf('0.9950058256237368748520459')
|
||
|
|
result = jcn(arg, arg)
|
||
|
|
assert(result.ae(res))
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
def test_jdn():
|
||
|
|
"""
|
||
|
|
Test some special cases of the dn(z, q) function.
|
||
|
|
"""
|
||
|
|
mp.dps = 100
|
||
|
|
|
||
|
|
# Abramowitz Table 16.5
|
||
|
|
# dn(0, q) = 1
|
||
|
|
mstring = str(random.random())
|
||
|
|
m = mpf(mstring)
|
||
|
|
|
||
|
|
dn = jdn(zero, m)
|
||
|
|
assert(dn.ae(one))
|
||
|
|
|
||
|
|
mp.dps = 25
|
||
|
|
# N[JacobiDN[1/10, 1/10], 25]
|
||
|
|
res = mpf('0.9995017055025556219713297')
|
||
|
|
arg = one/10
|
||
|
|
result = jdn(arg, arg)
|
||
|
|
assert(result.ae(res))
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
|
||
|
|
def test_sn_cn_dn_identities():
|
||
|
|
"""
|
||
|
|
Tests the some of the jacobi elliptic function identities found
|
||
|
|
on Mathworld. Haven't found in Abramowitz.
|
||
|
|
"""
|
||
|
|
mp.dps = 100
|
||
|
|
N = 5
|
||
|
|
for i in range(N):
|
||
|
|
qstring = str(random.random())
|
||
|
|
q = mpf(qstring)
|
||
|
|
zstring = str(100*random.random())
|
||
|
|
z = mpf(zstring)
|
||
|
|
|
||
|
|
# MathWorld
|
||
|
|
# sn(z, q)**2 + cn(z, q)**2 == 1
|
||
|
|
term1 = jsn(z, q)**2
|
||
|
|
term2 = jcn(z, q)**2
|
||
|
|
equality = one - term1 - term2
|
||
|
|
assert(equality.ae(0))
|
||
|
|
|
||
|
|
# MathWorld
|
||
|
|
# k**2 * sn(z, m)**2 + dn(z, m)**2 == 1
|
||
|
|
for i in range(N):
|
||
|
|
mstring = str(random.random())
|
||
|
|
m = mpf(qstring)
|
||
|
|
k = m.sqrt()
|
||
|
|
zstring = str(10*random.random())
|
||
|
|
z = mpf(zstring)
|
||
|
|
term1 = k**2 * jsn(z, m)**2
|
||
|
|
term2 = jdn(z, m)**2
|
||
|
|
equality = one - term1 - term2
|
||
|
|
assert(equality.ae(0))
|
||
|
|
|
||
|
|
|
||
|
|
for i in range(N):
|
||
|
|
mstring = str(random.random())
|
||
|
|
m = mpf(mstring)
|
||
|
|
k = m.sqrt()
|
||
|
|
zstring = str(random.random())
|
||
|
|
z = mpf(zstring)
|
||
|
|
|
||
|
|
# MathWorld
|
||
|
|
# k**2 * cn(z, m)**2 + (1 - k**2) = dn(z, m)**2
|
||
|
|
term1 = k**2 * jcn(z, m)**2
|
||
|
|
term2 = 1 - k**2
|
||
|
|
term3 = jdn(z, m)**2
|
||
|
|
equality = term3 - term1 - term2
|
||
|
|
assert(equality.ae(0))
|
||
|
|
|
||
|
|
K = ellipk(k**2)
|
||
|
|
# Abramowitz Table 16.5
|
||
|
|
# sn(K, m) = 1; K is K(k), first complete elliptic integral
|
||
|
|
r = jsn(K, m)
|
||
|
|
assert(r.ae(one))
|
||
|
|
|
||
|
|
# Abramowitz Table 16.5
|
||
|
|
# cn(K, q) = 0; K is K(k), first complete elliptic integral
|
||
|
|
equality = jcn(K, m)
|
||
|
|
assert(equality.ae(0))
|
||
|
|
|
||
|
|
# Abramowitz Table 16.6.3
|
||
|
|
# dn(z, 0) = 1, m == 0
|
||
|
|
z = m
|
||
|
|
value = jdn(z, zero)
|
||
|
|
assert(value.ae(one))
|
||
|
|
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
def test_sn_cn_dn_complex():
|
||
|
|
mp.dps = 30
|
||
|
|
# N[JacobiSN[1/4 + I/8, 1/3 + I/7], 35] in Mathematica
|
||
|
|
res = mpf('0.2495674401066275492326652143537') + \
|
||
|
|
mpf('0.12017344422863833381301051702823') * j
|
||
|
|
u = mpf(1)/4 + j/8
|
||
|
|
m = mpf(1)/3 + j/7
|
||
|
|
r = jsn(u, m)
|
||
|
|
assert(mpc_ae(r, res))
|
||
|
|
|
||
|
|
#N[JacobiCN[1/4 + I/8, 1/3 + I/7], 35]
|
||
|
|
res = mpf('0.9762691700944007312693721148331') - \
|
||
|
|
mpf('0.0307203994181623243583169154824')*j
|
||
|
|
r = jcn(u, m)
|
||
|
|
#assert r.real.ae(res.real)
|
||
|
|
#assert r.imag.ae(res.imag)
|
||
|
|
assert(mpc_ae(r, res))
|
||
|
|
|
||
|
|
#N[JacobiDN[1/4 + I/8, 1/3 + I/7], 35]
|
||
|
|
res = mpf('0.99639490163039577560547478589753039') - \
|
||
|
|
mpf('0.01346296520008176393432491077244994')*j
|
||
|
|
r = jdn(u, m)
|
||
|
|
assert(mpc_ae(r, res))
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
def test_elliptic_integrals():
|
||
|
|
# Test cases from Carlson's paper
|
||
|
|
mp.dps = 15
|
||
|
|
assert elliprd(0,2,1).ae(1.7972103521033883112)
|
||
|
|
assert elliprd(2,3,4).ae(0.16510527294261053349)
|
||
|
|
assert elliprd(j,-j,2).ae(0.65933854154219768919)
|
||
|
|
assert elliprd(0,j,-j).ae(1.2708196271909686299 + 2.7811120159520578777j)
|
||
|
|
assert elliprd(0,j-1,j).ae(-1.8577235439239060056 - 0.96193450888838559989j)
|
||
|
|
assert elliprd(-2-j,-j,-1+j).ae(1.8249027393703805305 - 1.2218475784827035855j)
|
||
|
|
# extra test cases
|
||
|
|
assert elliprg(0,0,0) == 0
|
||
|
|
assert elliprg(0,0,16).ae(2)
|
||
|
|
assert elliprg(0,16,0).ae(2)
|
||
|
|
assert elliprg(16,0,0).ae(2)
|
||
|
|
assert elliprg(1,4,0).ae(1.2110560275684595248036)
|
||
|
|
assert elliprg(1,0,4).ae(1.2110560275684595248036)
|
||
|
|
assert elliprg(0,4,1).ae(1.2110560275684595248036)
|
||
|
|
# should be symmetric -- fixes a bug present in the paper
|
||
|
|
x,y,z = 1,1j,-1+1j
|
||
|
|
assert elliprg(x,y,z).ae(0.64139146875812627545 + 0.58085463774808290907j)
|
||
|
|
assert elliprg(x,z,y).ae(0.64139146875812627545 + 0.58085463774808290907j)
|
||
|
|
assert elliprg(y,x,z).ae(0.64139146875812627545 + 0.58085463774808290907j)
|
||
|
|
assert elliprg(y,z,x).ae(0.64139146875812627545 + 0.58085463774808290907j)
|
||
|
|
assert elliprg(z,x,y).ae(0.64139146875812627545 + 0.58085463774808290907j)
|
||
|
|
assert elliprg(z,y,x).ae(0.64139146875812627545 + 0.58085463774808290907j)
|
||
|
|
|
||
|
|
for n in [5, 15, 30, 60, 100]:
|
||
|
|
mp.dps = n
|
||
|
|
assert elliprf(1,2,0).ae('1.3110287771460599052324197949455597068413774757158115814084108519003952935352071251151477664807145467230678763')
|
||
|
|
assert elliprf(0.5,1,0).ae('1.854074677301371918433850347195260046217598823521766905585928045056021776838119978357271861650371897277771871')
|
||
|
|
assert elliprf(j,-j,0).ae('1.854074677301371918433850347195260046217598823521766905585928045056021776838119978357271861650371897277771871')
|
||
|
|
assert elliprf(j-1,j,0).ae(mpc('0.79612586584233913293056938229563057846592264089185680214929401744498956943287031832657642790719940442165621412',
|
||
|
|
'-1.2138566698364959864300942567386038975419875860741507618279563735753073152507112254567291141460317931258599889'))
|
||
|
|
assert elliprf(2,3,4).ae('0.58408284167715170669284916892566789240351359699303216166309375305508295130412919665541330837704050454472379308')
|
||
|
|
assert elliprf(j,-j,2).ae('1.0441445654064360931078658361850779139591660747973017593275012615517220315993723776182276555339288363064476126')
|
||
|
|
assert elliprf(j-1,j,1-j).ae(mpc('0.93912050218619371196624617169781141161485651998254431830645241993282941057500174238125105410055253623847335313',
|
||
|
|
'-0.53296252018635269264859303449447908970360344322834582313172115220559316331271520508208025270300138589669326136'))
|
||
|
|
assert elliprc(0,0.25).ae(+pi)
|
||
|
|
assert elliprc(2.25,2).ae(+ln2)
|
||
|
|
assert elliprc(0,j).ae(mpc('1.1107207345395915617539702475151734246536554223439225557713489017391086982748684776438317336911913093408525532',
|
||
|
|
'-1.1107207345395915617539702475151734246536554223439225557713489017391086982748684776438317336911913093408525532'))
|
||
|
|
assert elliprc(-j,j).ae(mpc('1.2260849569072198222319655083097718755633725139745941606203839524036426936825652935738621522906572884239069297',
|
||
|
|
'-0.34471136988767679699935618332997956653521218571295874986708834375026550946053920574015526038040124556716711353'))
|
||
|
|
assert elliprc(0.25,-2).ae(ln2/3)
|
||
|
|
assert elliprc(j,-1).ae(mpc('0.77778596920447389875196055840799837589537035343923012237628610795937014001905822029050288316217145443865649819',
|
||
|
|
'0.1983248499342877364755170948292130095921681309577950696116251029742793455964385947473103628983664877025779304'))
|
||
|
|
assert elliprj(0,1,2,3).ae('0.77688623778582332014190282640545501102298064276022952731669118325952563819813258230708177398475643634103990878')
|
||
|
|
assert elliprj(2,3,4,5).ae('0.14297579667156753833233879421985774801466647854232626336218889885463800128817976132826443904216546421431528308')
|
||
|
|
assert elliprj(2,3,4,-1+j).ae(mpc('0.13613945827770535203521374457913768360237593025944342652613569368333226052158214183059386307242563164036672709',
|
||
|
|
'-0.38207561624427164249600936454845112611060375760094156571007648297226090050927156176977091273224510621553615189'))
|
||
|
|
assert elliprj(j,-j,0,2).ae('1.6490011662710884518243257224860232300246792717163891216346170272567376981346412066066050103935109581019055806')
|
||
|
|
assert elliprj(-1+j,-1-j,1,2).ae('0.94148358841220238083044612133767270187474673547917988681610772381758628963408843935027667916713866133196845063')
|
||
|
|
assert elliprj(j,-j,0,1-j).ae(mpc('1.8260115229009316249372594065790946657011067182850435297162034335356430755397401849070610280860044610878657501',
|
||
|
|
'1.2290661908643471500163617732957042849283739403009556715926326841959667290840290081010472716420690899886276961'))
|
||
|
|
assert elliprj(-1+j,-1-j,1,-3+j).ae(mpc('-0.61127970812028172123588152373622636829986597243716610650831553882054127570542477508023027578037045504958619422',
|
||
|
|
'-1.0684038390006807880182112972232562745485871763154040245065581157751693730095703406209466903752930797510491155'))
|
||
|
|
assert elliprj(-1+j,-2-j,-j,-1+j).ae(mpc('1.8249027393703805304622013339009022294368078659619988943515764258335975852685224202567854526307030593012768954',
|
||
|
|
'-1.2218475784827035854568450371590419833166777535029296025352291308244564398645467465067845461070602841312456831'))
|
||
|
|
|
||
|
|
assert elliprg(0,16,16).ae(+pi)
|
||
|
|
assert elliprg(2,3,4).ae('1.7255030280692277601061148835701141842692457170470456590515892070736643637303053506944907685301315299153040991')
|
||
|
|
assert elliprg(0,j,-j).ae('0.42360654239698954330324956174109581824072295516347109253028968632986700241706737986160014699730561497106114281')
|
||
|
|
assert elliprg(j-1,j,0).ae(mpc('0.44660591677018372656731970402124510811555212083508861036067729944477855594654762496407405328607219895053798354',
|
||
|
|
'0.70768352357515390073102719507612395221369717586839400605901402910893345301718731499237159587077682267374159282'))
|
||
|
|
assert elliprg(-j,j-1,j).ae(mpc('0.36023392184473309033675652092928695596803358846377334894215349632203382573844427952830064383286995172598964266',
|
||
|
|
'0.40348623401722113740956336997761033878615232917480045914551915169013722542827052849476969199578321834819903921'))
|
||
|
|
assert elliprg(0, mpf('0.0796'), 4).ae('1.0284758090288040009838871385180217366569777284430590125081211090574701293154645750017813190805144572673802094')
|
||
|
|
mp.dps = 15
|
||
|
|
|
||
|
|
# more test cases for the branch of ellippi / elliprj
|
||
|
|
assert elliprj(-1-0.5j, -10-6j, -10-3j, -5+10j).ae(0.128470516743927699 + 0.102175950778504625j, abs_eps=1e-8)
|
||
|
|
assert elliprj(1.987, 4.463 - 1.614j, 0, -3.965).ae(-0.341575118513811305 - 0.394703757004268486j, abs_eps=1e-8)
|
||
|
|
assert elliprj(0.3068, -4.037+0.632j, 1.654, -0.9609).ae(-1.14735199581485639 - 0.134450158867472264j, abs_eps=1e-8)
|
||
|
|
assert elliprj(0.3068, -4.037-0.632j, 1.654, -0.9609).ae(1.758765901861727 - 0.161002343366626892j, abs_eps=1e-5)
|
||
|
|
assert elliprj(0.3068, -4.037+0.0632j, 1.654, -0.9609).ae(-1.17157627949475577 - 0.069182614173988811j, abs_eps=1e-8)
|
||
|
|
assert elliprj(0.3068, -4.037+0.00632j, 1.654, -0.9609).ae(-1.17337595670549633 - 0.0623069224526925j, abs_eps=1e-8)
|
||
|
|
|
||
|
|
# these require accurate integration
|
||
|
|
assert elliprj(0.3068, -4.037-0.0632j, 1.654, -0.9609).ae(1.77940452391261626 + 0.0388711305592447234j)
|
||
|
|
assert elliprj(0.3068, -4.037-0.00632j, 1.654, -0.9609).ae(1.77806722756403055 + 0.0592749824572262329j)
|
||
|
|
# issue #571
|
||
|
|
assert ellippi(2.1 + 0.94j, 2.3 + 0.98j, 2.5 + 0.01j).ae(-0.40652414240811963438 + 2.1547659461404749309j)
|
||
|
|
|
||
|
|
assert ellippi(2.0-1.0j, 2.0+1.0j).ae(1.8578723151271115 - 1.18642180609983531j)
|
||
|
|
assert ellippi(2.0-0.5j, 0.5+1.0j).ae(0.936761970766645807 - 1.61876787838890786j)
|
||
|
|
assert ellippi(2.0, 1.0+1.0j).ae(0.999881420735506708 - 2.4139272867045391j)
|
||
|
|
assert ellippi(2.0+1.0j, 2.0-1.0j).ae(1.8578723151271115 + 1.18642180609983531j)
|
||
|
|
assert ellippi(2.0+1.0j, 2.0).ae(2.78474654927885845 + 2.02204728966993314j)
|
||
|
|
|
||
|
|
def test_issue_238():
|
||
|
|
assert isnan(qfrom(m=nan))
|