# Conflicts:
#	wafo/misc.py
master
Per A Brodtkorb 9 years ago
commit e5a325d024

@ -35,7 +35,7 @@ before_install:
- sudo apt-get install gfortran
# Install packages
install:
- conda install --yes python=$TRAVIS_PYTHON_VERSION numpy scipy pytest numdifftools matplotlib nose
- conda install --yes python=$TRAVIS_PYTHON_VERSION numpy scipy pytest numdifftools matplotlib nose pytest-pep8 pytest-cov mpmath
- pip install coveralls
- pip install codecov
- python setup.py build
@ -47,6 +47,7 @@ before_script:
- git config --global user.name "pbrod"
script:
- coverage run --source=wafo setup.py test
- py.test wafo/ --cov --pep8 --doctest-modules
after_success:
- coveralls
- codecov

@ -64,6 +64,7 @@ addopts =
addopts =
--cov wafo --cov-report term-missing
--verbose
--doctest-modules
[aliases]
docs = build_sphinx

@ -0,0 +1,577 @@
'''
Created on 20. aug. 2015
@author: pab
'''
from __future__ import division
import numpy as np
import warnings
import numdifftools as nd # @UnresolvedImport
import numdifftools.nd_algopy as nda # @UnresolvedImport
from numdifftools.limits import Limit # @UnresolvedImport
from numpy import linalg
from numpy.polynomial.chebyshev import chebval, Chebyshev
from numpy.polynomial import polynomial
from wafo.misc import piecewise, findcross, ecross
from collections import namedtuple
EPS = np.finfo(float).eps
_EPS = EPS
finfo = np.finfo(float)
_TINY = finfo.tiny
_HUGE = finfo.max
dea3 = nd.dea3
class PolyBasis(object):
def derivative(self, t, k, n=1):
c = np.zeros(k + 1)
c[k] = 1
dc = polynomial.polyder(c, m=n)
return polynomial.polyval(t, dc)
def eval(self, t, c):
return polynomial.polyval(t, c)
def __call__(self, t, k):
return t**k
poly_basis = PolyBasis()
class ChebyshevBasis(object):
def derivative(self, t, k, n=1):
c = np.zeros(k + 1)
c[k] = 1
cheb = Chebyshev(c)
dcheb = cheb.deriv(m=n)
return chebval(t, dcheb.coef)
def eval(self, t, c):
return chebval(t, c)
def __call__(self, t, k):
c = np.zeros(k + 1)
c[k] = 1
return chebval(t, c)
chebyshev_basis = ChebyshevBasis()
def richardson(Q, k):
# license BSD
# Richardson extrapolation with parameter estimation
c = np.real((Q[k - 1] - Q[k - 2]) / (Q[k] - Q[k - 1])) - 1.
# The lower bound 0.07 admits the singularity x.^-0.9
c = max(c, 0.07)
R = Q[k] + (Q[k] - Q[k - 1]) / c
return R
def evans_webster_weights(omega, gg, dgg, x, basis, *args, **kwds):
def Psi(t, k):
return dgg(t, *args, **kwds) * basis(t, k)
j_w = 1j * omega
nn = len(x)
A = np.zeros((nn, nn), dtype=complex)
F = np.zeros((nn,), dtype=complex)
dbasis = basis.derivative
lim_gg = Limit(gg)
b1 = np.exp(j_w*lim_gg(1, *args, **kwds))
if np.isnan(b1):
b1 = 0.0
a1 = np.exp(j_w*lim_gg(-1, *args, **kwds))
if np.isnan(a1):
a1 = 0.0
lim_Psi = Limit(Psi)
for k in range(nn):
F[k] = basis(1, k)*b1 - basis(-1, k)*a1
A[k] = (dbasis(x, k, n=1) + j_w * lim_Psi(x, k))
LS = linalg.lstsq(A, F)
return LS[0]
def osc_weights(omega, g, dg, x, basis, ab, *args, **kwds):
w = []
for a, b in zip(ab[::2], ab[1::2]):
scale = (b - a) / 2
offset = (a + b) / 2
def gg(t):
return g(scale * t + offset, *args, **kwds)
def dgg(t):
return scale * dg(scale * t + offset, *args, **kwds)
w.append(evans_webster_weights(omega, gg, dgg, x, basis))
return np.asarray(w).ravel()
class QuadOsc(object):
info = namedtuple('info', ['error_estimate', 'n'])
def __init__(self, f, g, dg=None, a=-1, b=1, basis=chebyshev_basis, s=15,
precision=10, endpoints=False, maxiter=17, full_output=False):
self.f = f
self.g = g
self.dg = nd.Derivative(g) if dg is None else dg
self.basis = basis
self.a = a
self.b = b
self.s = s
self.endpoints = endpoints
self.maxiter = maxiter
self.precision = precision
self.full_output = full_output
def _change_interval_to_0_1(self, f, g, dg, a, b):
def f1(t, *args, **kwds):
den = 1-t
return f(a + t / den, *args, **kwds) / den ** 2
def g1(t, *args, **kwds):
return g(a + t / (1 - t), *args, **kwds)
def dg1(t, *args, **kwds):
den = 1-t
return dg(a + t / den, *args, **kwds) / den ** 2
return f1, g2, dg1, 0., 1.
def _change_interval_to_m1_0(self, f, g, dg, a, b):
def f2(t, *args, **kwds):
den = 1 + t
return f(b + t / den, *args, **kwds) / den ** 2
def g2(t, *args, **kwds):
return g(b + t / (1 + t), *args, **kwds)
def dg2(t, *args, **kwds):
den = 1 + t
return dg(b + t / den, *args, **kwds) / den ** 2
return f2, g2, dg2, -1.0, 0.0
def _change_interval_to_m1_1(self, f, g, dg, a, b):
def f2(t, *args, **kwds):
den = (1 - t**2)
return f(t / den, *args, **kwds) * (1+t**2) / den ** 2
def g2(t, *args, **kwds):
den = (1 - t**2)
return g(t / den, *args, **kwds)
def dg2(t, *args, **kwds):
den = (1 - t**2)
return dg(t / den, *args, **kwds) * (1+t**2) / den ** 2
return f2, g2, dg2, -1., 1.
def _get_functions(self):
a, b = self.a, self.b
reverse = np.real(a) > np.real(b)
if reverse:
a, b = b, a
f, g, dg = self.f, self.g, self.dg
if a == b:
pass
elif np.isinf(a) | np.isinf(b):
# Check real limits
if ~np.isreal(a) | ~np.isreal(b) | np.isnan(a) | np.isnan(b):
raise ValueError('Infinite intervals must be real.')
# Change of variable
if np.isfinite(a) & np.isinf(b):
f, g, dg, a, b = self._change_interval_to_0_1(f, g, dg, a, b)
elif np.isinf(a) & np.isfinite(b):
f, g, dg, a, b = self._change_interval_to_m1_0(f, g, dg, a, b)
else: # -inf to inf
f, g, dg, a, b = self._change_interval_to_m1_1(f, g, dg, a, b)
return f, g, dg, a, b, reverse
def __call__(self, omega, *args, **kwds):
f, g, dg, a, b, reverse = self._get_functions()
Q, err = self._quad_osc(f, g, dg, a, b, omega, *args, **kwds)
if reverse:
Q = -Q
if self.full_output:
return Q, err
return Q
def _get_best_estimate(self, k, Q0, Q1, Q2):
if k >= 5:
Qv = np.hstack((Q0[k], Q1[k], Q2[k]))
Qw = np.hstack((Q0[k - 1], Q1[k - 1], Q2[k - 1]))
elif k >= 3:
Qv = np.hstack((Q0[k], Q1[k]))
Qw = np.hstack((Q0[k - 1], Q1[k - 1]))
else:
Qv = np.atleast_1d(Q0[k])
Qw = Q0[k - 1]
errors = np.atleast_1d(abs(Qv - Qw))
j = np.nanargmin(errors)
return Qv[j], errors[j]
def _extrapolate(self, k, Q0, Q1, Q2):
if k >= 4:
Q1[k], _err1 = dea3(Q0[k - 2], Q0[k - 1], Q0[k])
Q2[k], _err2 = dea3(Q1[k - 2], Q1[k - 1], Q1[k])
elif k >= 2:
Q1[k], _err1 = dea3(Q0[k - 2], Q0[k - 1], Q0[k])
# # Richardson extrapolation
# if k >= 4:
# Q1[k] = richardson(Q0, k)
# Q2[k] = richardson(Q1, k)
# elif k >= 2:
# Q1[k] = richardson(Q0, k)
Q, err = self._get_best_estimate(k, Q0, Q1, Q2)
return Q, err
def _quad_osc(self, f, g, dg, a, b, omega, *args, **kwds):
if a == b:
Q = b - a
err = b - a
return Q, err
abseps = 10**-self.precision
max_iter = self.maxiter
basis = self.basis
if self.endpoints:
xq = chebyshev_extrema(self.s)
else:
xq = chebyshev_roots(self.s)
# xq = tanh_sinh_open_nodes(self.s)
# One interval
hh = (b - a) / 2
x = (a + b) / 2 + hh * xq # Nodes
dtype = complex
Q0 = np.zeros((max_iter, 1), dtype=dtype) # Quadrature
Q1 = np.zeros((max_iter, 1), dtype=dtype) # First extrapolation
Q2 = np.zeros((max_iter, 1), dtype=dtype) # Second extrapolation
lim_f = Limit(f)
ab = np.hstack([a, b])
wq = osc_weights(omega, g, dg, xq, basis, ab, *args, **kwds)
Q0[0] = hh * np.sum(wq * lim_f(x, *args, **kwds))
# Successive bisection of intervals
nq = len(xq)
n = nq
for k in xrange(1, max_iter):
n += nq*2**k
hh = hh / 2
x = np.hstack([x + a, x + b]) / 2
ab = np.hstack([ab + a, ab + b]) / 2
wq = osc_weights(omega, g, dg, xq, basis, ab, *args, **kwds)
Q0[k] = hh * np.sum(wq * lim_f(x, *args, **kwds))
Q, err = self._extrapolate(k, Q0, Q1, Q2)
convergence = (err <= abseps) | ~np.isfinite(Q)
if convergence:
break
else:
warnings.warn('Max number of iterations reached '
'without convergence.')
if ~np.isfinite(Q):
warnings.warn('Integral approximation is Infinite or NaN.')
# The error estimate should not be zero
err += 2 * np.finfo(Q).eps
return Q, self.info(err, n)
def adaptive_levin_points(M, delta):
m = M - 1
prm = 0.5
while prm * m / delta >= 1:
delta = 2 * delta
k = np.arange(M)
x = piecewise([k < prm * m, k == np.ceil(prm * m)],
[-1 + k / delta, 0 * k, 1 - (m - k) / delta])
return x
def open_levin_points(M, delta):
return adaptive_levin_points(M+2, delta)[1:-1]
def chebyshev_extrema(M, delta=None):
k = np.arange(M)
x = np.cos(k * np.pi / (M-1))
return x
_EPS = np.finfo(float).eps
def tanh_sinh_nodes(M, delta=None, tol=_EPS):
tmax = np.arcsinh(np.arctanh(1-_EPS)*2/np.pi)
# tmax = 3.18
m = int(np.floor(-np.log2(tmax/max(M-1, 1)))) - 1
h = 2.0**-m
t = np.arange((M+1)//2+1)*h
x = np.tanh(np.pi/2*np.sinh(t))
k = np.flatnonzero(np.abs(x - 1) <= 10*tol)
y = x[:k[0]+1] if len(k) else x
return np.hstack((-y[:0:-1], y))
def tanh_sinh_open_nodes(M, delta=None, tol=_EPS):
return tanh_sinh_nodes(M+1, delta, tol)[1:-1]
def chebyshev_roots(M, delta=None):
k = np.arange(1, 2*M, 2) * 0.5
x = np.cos(k * np.pi / M)
return x
class AdaptiveLevin(object):
'''Return integral for the Levin-type and adaptive Levin-type methods'''
info = namedtuple('info', ['error_estimate', 'n'])
def __init__(self, f, g, dg=None, a=-1, b=1, basis=chebyshev_basis, s=1,
precision=10, endpoints=True, full_output=False):
self.f = f
self.g = g
self.dg = nd.Derivative(g) if dg is None else dg
self.basis = basis
self.a = a
self.b = b
self.s = s
self.precision = precision
self.endpoints = endpoints
self.full_output = full_output
def aLevinTQ(self, omega, ff, gg, dgg, x, s, basis, *args, **kwds):
def Psi(t, k):
return dgg(t, *args, **kwds) * basis(t, k)
j_w = 1j * omega
nu = np.ones((len(x),), dtype=int)
nu[0] = nu[-1] = s
S = np.cumsum(np.hstack((nu, 0)))
S[-1] = 0
nn = int(S[-2])
A = np.zeros((nn, nn), dtype=complex)
F = np.zeros((nn,))
dff = Limit(nda.Derivative(ff))
dPsi = Limit(nda.Derivative(Psi))
dbasis = basis.derivative
for r, t in enumerate(x):
for j in range(S[r - 1], S[r]):
order = ((j - S[r - 1]) % nu[r]) # derivative order
dff.f.n = order
F[j] = dff(t, *args, **kwds)
dPsi.f.n = order
for k in range(nn):
A[j, k] = (dbasis(t, k, n=order+1) + j_w * dPsi(t, k))
k1 = np.flatnonzero(1-np.isfinite(F))
if k1.size > 0: # Remove singularities
warnings.warn('Singularities detected! ')
A[k1] = 0
F[k1] = 0
LS = linalg.lstsq(A, F)
v = basis.eval([-1, 1], LS[0])
lim_gg = Limit(gg)
gb = np.exp(j_w * lim_gg(1, *args, **kwds))
if np.isnan(gb):
gb = 0
ga = np.exp(j_w * lim_gg(-1, *args, **kwds))
if np.isnan(ga):
ga = 0
NR = (v[1] * gb - v[0] * ga)
return NR
def _get_integration_limits(self, omega, args, kwds):
a, b = self.a, self.b
M = 30
ab = [a]
scale = (b - a) / 2
n = 30
x = np.linspace(a, b, n + 1)
dg_x = np.asarray([scale * omega * self.dg(xi, *args, **kwds)
for xi in x])
i10 = findcross(dg_x, M)
i1 = findcross(dg_x, 1)
i0 = findcross(dg_x, 0)
im1 = findcross(dg_x, -1)
im10 = findcross(dg_x, -M)
x10 = ecross(x, dg_x, i10, M) if len(i10) else ()
x1 = ecross(x, dg_x, i1, 1) if len(i1) else ()
x0 = ecross(x, dg_x, i0, 0) if len(i0) else ()
xm1 = ecross(x, dg_x, im1, -1) if len(im1) else ()
xm10 = ecross(x, dg_x, im10, -M) if len(im10) else ()
for i in np.unique(np.hstack((x10, x1, x0, xm1, xm10))):
if x[0] < i < x[n]:
ab.append(i)
ab.append(b)
return ab
def __call__(self, omega, *args, **kwds):
ab = self._get_integration_limits(omega, args, kwds)
s = self.s
val = 0
n = 0
err = 0
for ai, bi in zip(ab[:-1], ab[1:]):
vali, infoi = self._QaL(s, ai, bi, omega, *args, **kwds)
val += vali
err += infoi.error_estimate
n += infoi.n
if self.full_output:
info = self.info(err, n)
return val, info
return val
def _get_num_points(self, s, prec, betam):
return 1 if s > 1 else int(prec / max(np.log10(betam + 1), 1) + 1)
def _QaL(self, s, a, b, omega, *args, **kwds):
'''if s>1,the integral is computed by Q_s^L'''
scale = (b - a) / 2
offset = (a + b) / 2
prec = self.precision # desired precision
def ff(t, *args, **kwds):
return scale * self.f(scale * t + offset, *args, **kwds)
def gg(t, *args, **kwds):
return self.g(scale * t + offset, *args, **kwds)
def dgg(t, *args, **kwds):
return scale * self.dg(scale * t + offset, *args, **kwds)
dg_a = abs(omega * dgg(-1, *args, **kwds))
dg_b = abs(omega * dgg(1, *args, **kwds))
g_a = abs(omega * gg(-1, *args, **kwds))
g_b = abs(omega * gg(1, *args, **kwds))
delta, alpha = min(dg_a, dg_b), min(g_a, g_b)
betam = delta # * scale
if self.endpoints:
if (delta < 10 or alpha <= 10 or s > 1):
points = chebyshev_extrema
else:
points = adaptive_levin_points
elif (delta < 10 or alpha <= 10 or s > 1):
points = chebyshev_roots
else:
points = open_levin_points # tanh_sinh_open_nodes
m = self._get_num_points(s, prec, betam)
abseps = 10*10.0**-prec
num_collocation_point_list = m*2**np.arange(1, 5) + 1
basis = self.basis
Q = 1e+300
n = 0
ni = 0
for num_collocation_points in num_collocation_point_list:
ni_old = ni
Q_old = Q
x = points(num_collocation_points, betam)
ni = len(x)
if ni > ni_old:
Q = self.aLevinTQ(omega, ff, gg, dgg, x, s, basis, *args,
**kwds)
n += ni
err = np.abs(Q-Q_old)
if err <= abseps:
break
info = self.info(err, n)
return Q, info
class EvansWebster(AdaptiveLevin):
'''Return integral for the Evans Webster method'''
def __init__(self, f, g, dg=None, a=-1, b=1, basis=chebyshev_basis, s=8,
precision=10, endpoints=False, full_output=False):
self.f = f
self.g = g
self.dg = nd.Derivative(g) if dg is None else dg
self.basis = basis
self.a = a
self.b = b
self.s = s
self.endpoints = endpoints
self.precision = precision
self.full_output = full_output
def aLevinTQ(self, omega, ff, gg, dgg, x, s, basis, *args, **kwds):
w = evans_webster_weights(omega, gg, dgg, x, basis, *args, **kwds)
f = Limit(ff)(x, *args, **kwds)
NR = np.sum(f*w)
return NR
def _get_num_points(self, s, prec, betam):
return 8 if s > 1 else int(prec / max(np.log10(betam + 1), 1) + 1)
# def _QaL(self, s, a, b, omega, *args, **kwds):
# '''if s>1,the integral is computed by Q_s^L'''
# scale = (b - a) / 2
# offset = (a + b) / 2
# prec = self.precision # desired precision
#
# def ff(t, *args, **kwds):
# return scale * self.f(scale * t + offset, *args, **kwds)
#
# def gg(t, *args, **kwds):
# return self.g(scale * t + offset, *args, **kwds)
#
# def dgg(t, *args, **kwds):
# return scale * self.dg(scale * t + offset, *args, **kwds)
# dg_a = abs(omega * dgg(-1, *args, **kwds))
# dg_b = abs(omega * dgg(1, *args, **kwds))
# g_a = abs(omega * gg(-1, *args, **kwds))
# g_b = abs(omega * gg(1, *args, **kwds))
# delta, alpha = min(dg_a, dg_b), min(g_a, g_b)
#
# betam = delta # * scale
# if self.endpoints:
# if (delta < 10 or alpha <= 10 or s > 1):
# points = chebyshev_extrema
# else:
# points = adaptive_levin_points
# elif (delta < 10 or alpha <= 10 or s > 1):
# points = chebyshev_roots
# else:
# points = tanh_sinh_open_nodes
#
# m = 8 if s > 1 else int(prec / max(np.log10(betam + 1), 1) + 1)
# abseps = 10*10.0**-prec
# num_collocation_point_list = 2*m*np.arange(1, 6, 2)
# # range(num_points, num_points+3, 2)
# basis = self.basis
# Q = 1e+300
# n = 0
# for num_collocation_points in num_collocation_point_list:
# Q_old = Q
# x = points(num_collocation_points-1, betam)
# Q = self.aLevinTQ(omega, ff, gg, dgg, x, s, basis, *args, **kwds)
# n += num_collocation_points
# err = np.abs(Q-Q_old)
# if err <= abseps:
# break
# info = self.info(err, n)
# return Q, info
if __name__ == '__main__':
tanh_sinh_nodes(16)

@ -62,8 +62,6 @@ def piecewise(condlist, funclist, xi=None, fill_value=0.0, args=(), **kw):
Parameters
----------
xi : tuple
input arguments to the functions in funclist, i.e., (x0, x1,...., xn)
condlist : list of bool arrays
Each boolean array corresponds to a function in `funclist`. Wherever
`condlist[i]` is True, `funclist[i](x0,x1,...,xn)` is used as the
@ -80,6 +78,8 @@ def piecewise(condlist, funclist, xi=None, fill_value=0.0, args=(), **kw):
or a scalar value as output. If, instead of a callable,
a scalar is provided then a constant function (``lambda x: scalar``) is
assumed.
xi : tuple
input arguments to the functions in funclist, i.e., (x0, x1,...., xn)
fill_value : scalar
fill value for out of range values. Default 0.
args : tuple, optional
@ -160,22 +160,23 @@ def piecewise(condlist, funclist, xi=None, fill_value=0.0, args=(), **kw):
condlist = np.broadcast_arrays(*condlist)
if len(condlist) == len(funclist)-1:
condlist.append(otherwise_condition(condlist))
if xi is None:
arrays = ()
dtype = np.result_type(*funclist)
shape = condlist[0].shape
else:
if not isinstance(xi, tuple):
xi = (xi,)
arrays = np.broadcast_arrays(*xi)
dtype = np.result_type(*arrays)
shape = arrays[0].shape
out = valarray(condlist[0].shape, fill_value, dtype)
out = valarray(shape, fill_value, dtype)
for cond, func in zip(condlist, funclist):
if isinstance(func, Callable):
temp = tuple(np.extract(cond, arr) for arr in arrays) + args
np.place(out, cond, func(*temp, **kw))
else: # func is a scalar value or array
else: # func is a scalar value or a list
np.putmask(out, cond, func)
return out

@ -1,144 +0,0 @@
from operator import itemgetter as _itemgetter
from keyword import iskeyword as _iskeyword
import sys as _sys
def namedtuple(typename, field_names, verbose=False):
"""Returns a new subclass of tuple with named fields.
>>> Point = namedtuple('Point', 'x y')
>>> Point.__doc__ # docstring for the new class
'Point(x, y)'
>>> p = Point(11, y=22) # instantiate with positional args or keywords
>>> p[0] + p[1] # indexable like a plain tuple
33
>>> x, y = p # unpack like a regular tuple
>>> x, y
(11, 22)
>>> p.x + p.y # fields also accessable by name
33
>>> d = p._asdict() # convert to a dictionary
>>> d['x']
11
>>> Point(**d) # convert from a dictionary
Point(x=11, y=22)
>>> p._replace(x=100) # _replace() is like str.replace() but targets named fields
Point(x=100, y=22)
"""
# Parse and validate the field names. Validation serves two purposes,
# generating informative error messages and preventing template injection
# attacks.
if isinstance(field_names, basestring):
# names separated by whitespace and/or commas
field_names = field_names.replace(',', ' ').split()
field_names = tuple(field_names)
for name in (typename,) + field_names:
if not min(c.isalnum() or c == '_' for c in name):
raise ValueError(
'Type names and field names can only contain alphanumeric ' +
'characters and underscores: %r' % name)
if _iskeyword(name):
raise ValueError(
'Type names and field names cannot be a keyword: %r' % name)
if name[0].isdigit():
raise ValueError('Type names and field names cannot start ' +
'with a number: %r' % name)
seen_names = set()
for name in field_names:
if name.startswith('_'):
raise ValueError(
'Field names cannot start with an underscore: %r' % name)
if name in seen_names:
raise ValueError('Encountered duplicate field name: %r' % name)
seen_names.add(name)
# Create and fill-in the class template
numfields = len(field_names)
# tuple repr without parens or quotes
argtxt = repr(field_names).replace("'", "")[1:-1]
reprtxt = ', '.join('%s=%%r' % name for name in field_names)
dicttxt = ', '.join('%r: t[%d]' % (name, pos)
for pos, name in enumerate(field_names))
template = '''class %(typename)s(tuple):
'%(typename)s(%(argtxt)s)' \n
__slots__ = () \n
_fields = %(field_names)r \n
def __new__(cls, %(argtxt)s):
return tuple.__new__(cls, (%(argtxt)s)) \n
@classmethod
def _make(cls, iterable, new=tuple.__new__, len=len):
'Make a new %(typename)s object from a sequence or iterable'
result = new(cls, iterable)
if len(result) != %(numfields)d:
raise TypeError('Expected %(numfields)d arguments, got %%d' %% len(result))
return result \n
def __repr__(self):
return '%(typename)s(%(reprtxt)s)' %% self \n
def _asdict(t):
'Return a new dict which maps field names to their values'
return {%(dicttxt)s} \n
def _replace(self, **kwds):
'Return a new %(typename)s object replacing specified fields with new values'
result = self._make(map(kwds.pop, %(field_names)r, self))
if kwds:
raise ValueError('Got unexpected field names: %%r' %% kwds.keys())
return result \n\n''' % locals()
for i, name in enumerate(field_names):
template += ' %s = property(itemgetter(%d))\n' % (name, i)
if verbose:
print template
# Execute the template string in a temporary namespace
namespace = dict(itemgetter=_itemgetter)
try:
exec template in namespace
except SyntaxError, e:
raise SyntaxError(e.message + ':\n' + template)
result = namespace[typename]
# For pickling to work, the __module__ variable needs to be set to the
# frame where the named tuple is created. Bypass this step in enviroments
# where sys._getframe is not defined (Jython for example).
if hasattr(_sys, '_getframe'):
result.__module__ = _sys._getframe(1).f_globals['__name__']
return result
if __name__ == '__main__':
# verify that instances can be pickled
from cPickle import loads, dumps
Point = namedtuple('Point', 'x, y', True)
p = Point(x=10, y=20)
assert p == loads(dumps(p))
# test and demonstrate ability to override methods
class Point(namedtuple('Point', 'x y')):
@property
def hypot(self):
return (self.x ** 2 + self.y ** 2) ** 0.5
def __str__(self):
return 'Point: x=%6.3f y=%6.3f hypot=%6.3f' % (self.x, self.y,
self.hypot)
for p in Point(3, 4), Point(14, 5), Point(9. / 7, 6):
print(p)
class Point(namedtuple('Point', 'x y')):
'''Point class with optimized _make() and _replace()
without error-checking
'''
_make = classmethod(tuple.__new__)
def _replace(self, _map=map, **kwds):
return self._make(_map(kwds.get, ('x', 'y'), self))
print(Point(11, 22)._replace(x=100))
import doctest
TestResults = namedtuple('TestResults', 'failed attempted')
print(TestResults(*doctest.testmod()))

@ -0,0 +1,387 @@
'''
Created on 31. aug. 2015
@author: pab
'''
from __future__ import division
import numpy as np
import mpmath as mp
import unittest
from wafo.integrate_oscillating import (adaptive_levin_points,
chebyshev_extrema,
chebyshev_roots, tanh_sinh_nodes,
tanh_sinh_open_nodes,
AdaptiveLevin, poly_basis,
chebyshev_basis,
EvansWebster, QuadOsc)
# import numdifftools as nd
from numpy.testing import assert_allclose
from scipy.special import gamma, digamma
_EPS = np.finfo(float).eps
class TestBasis(unittest.TestCase):
def test_poly(self):
t = 1
vals = [poly_basis.derivative(t, k, n=1) for k in range(3)]
assert_allclose(vals, range(3))
vals = [poly_basis.derivative(0, k, n=1) for k in range(3)]
assert_allclose(vals, [0, 1, 0])
vals = [poly_basis.derivative(0, k, n=2) for k in range(3)]
assert_allclose(vals, [0, 0, 2])
def test_chebyshev(self):
t = 1
vals = [chebyshev_basis.derivative(t, k, n=1) for k in range(3)]
assert_allclose(vals, np.arange(3)**2)
vals = [chebyshev_basis.derivative(0, k, n=1) for k in range(3)]
assert_allclose(vals, [0, 1, 0])
vals = [chebyshev_basis.derivative(0, k, n=2) for k in range(3)]
assert_allclose(vals, [0, 0, 4])
class TestLevinPoints(unittest.TestCase):
def test_adaptive(self):
M = 11
delta = 100
x = adaptive_levin_points(M, delta)
true_x = [-1., -0.99, -0.98, -0.97, -0.96, 0.,
0.96, 0.97, 0.98, 0.99, 1.]
assert_allclose(x, true_x)
def test_chebyshev_extrema(self):
M = 11
delta = 100
x = chebyshev_extrema(M, delta)
true_x = [1.000000e+00, 9.510565e-01, 8.090170e-01, 5.877853e-01,
3.090170e-01, 6.123234e-17, -3.090170e-01, -5.877853e-01,
-8.090170e-01, -9.510565e-01, -1.000000e+00]
assert_allclose(x, true_x)
def test_chebyshev_roots(self):
M = 11
delta = 100
x = chebyshev_roots(M, delta)
true_x = [9.89821442e-01, 9.09631995e-01, 7.55749574e-01,
5.40640817e-01, 2.81732557e-01, 2.83276945e-16,
-2.81732557e-01, -5.40640817e-01, -7.55749574e-01,
-9.09631995e-01, -9.89821442e-01]
assert_allclose(x, true_x)
def test_tanh_sinh_nodes(self):
for n in 2**np.arange(1, 5) + 1:
x = tanh_sinh_nodes(n)
# self.assertEqual(n, len(x))
def test_tanh_sinh_open_nodes(self):
for n in 2**np.arange(1, 5) + 1:
x = tanh_sinh_open_nodes(n)
# self.assertEqual(n, len(x))
class LevinQuadrature(unittest.TestCase):
def test_exp_4t_exp_jw_gamma_t_exp_4t(self):
def f(t):
return np.exp(4 * t) # amplitude function
def g(t):
return t + np.exp(4 * t) * gamma(t) # phase function
def dg(t):
return 1 + (4 + digamma(t)) * np.exp(4 * t) * gamma(t)
a = 1
b = 2
omega = 100
def ftot(t):
exp4t = mp.exp(4*t)
return exp4t * mp.exp(1j * omega * (t+exp4t*mp.gamma(t)))
_true_val, _err = mp.quadts(ftot, [a, (a+b)/2, b], error=True)
true_val = 0.00435354129735323908804 + 0.00202865398517716214366j
# quad = AdaptiveLevin(f, g, dg, a=a, b=b, s=1, full_output=True)
for quadfun in [EvansWebster, QuadOsc, AdaptiveLevin]:
quad = quadfun(f, g, dg, a=a, b=b, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-11)
# assert_allclose(info.n, 9)
def test_exp_jw_t(self):
def g(t):
return t
def dg(t):
return np.ones(np.shape(t))
def true_F(t):
return np.exp(1j*omega*g(t))/(1j*omega)
val, _err = mp.quadts(g, [0, 1], error=True)
a = 1
b = 2
omega = 1
true_val = true_F(b)-true_F(a)
for quadfun in [QuadOsc, AdaptiveLevin, EvansWebster]:
quad = quadfun(dg, g, dg, a, b, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-12)
# assert_allclose(info.n, 21)
def test_I1_1_p_ln_x_exp_jw_xlnx(self):
def g(t):
return t*np.log(t)
def dg(t):
return 1 + np.log(t)
def true_F(t):
return np.exp(1j*(omega*g(t)))/(1j*omega)
a = 100
b = 200
omega = 1
true_val = true_F(b)-true_F(a)
for quadfun in [AdaptiveLevin, QuadOsc, EvansWebster]:
quad = quadfun(dg, g, dg, a, b, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-10)
# assert_allclose(info.n, 11)
def test_I4_ln_x_exp_jw_30x(self):
n = 7
def g(t):
return t**n
def dg(t):
return n*t**(n-1)
def f(t):
return dg(t)*np.log(g(t))
a = 0
b = (2 * np.pi)**(1./n)
omega = 30
def ftot(t):
return n*t**(n-1)*mp.log(t**n) * mp.exp(1j * omega * t**n)
_true_val, _err = mp.quadts(ftot, [a, b], error=True, maxdegree=8)
# true_val = (-0.052183048684992 - 0.193877275099872j)
true_val = (-0.0521830486849921 - 0.193877275099871j)
for quadfun in [QuadOsc, EvansWebster, AdaptiveLevin]:
quad = quadfun(f, g, dg, a, b, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-5)
def test_I5_coscost_sint_exp_jw_sint(self):
a = 0
b = np.pi/2
omega = 100
def f(t):
return np.cos(np.cos(t))*np.sin(t)
def g(t):
return np.sin(t)
def dg(t):
return np.cos(t)
def ftot(t):
return mp.cos(mp.cos(t)) * mp.sin(t) * mp.exp(1j * omega *
mp.sin(t))
_true_val, _err = mp.quadts(ftot, [a, 0.5, 1, b], maxdegree=9,
error=True)
true_val = 0.0325497765499959-0.121009052128827j
for quadfun in [QuadOsc, EvansWebster, AdaptiveLevin]:
quad = quadfun(f, g, dg, a, b, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-9)
def test_I6_exp_jw_td_1_m_t(self):
a = 0
b = 1
omega = 1
def f(t):
return np.ones(np.shape(t))
def g(t):
return t/(1-t)
def dg(t):
return 1./(1-t)**2
def ftot(t):
return mp.exp(1j * omega * t/(1-t))
true_val = (0.3785503757641866423607342717846606761068353230802945830 +
0.3433779615564270328325330038583124340012440194999075192j)
for quadfun in [QuadOsc, EvansWebster, AdaptiveLevin]:
quad = quadfun(f, g, dg, a, b, endpoints=False, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-10)
def test_I8_cos_47pix2d4_exp_jw_x(self):
def f(t):
return np.cos(47*np.pi/4*t**2)
def g(t):
return t
def dg(t):
return 1
a = -1
b = 1
omega = 451*np.pi/4
true_val = 2.3328690362927e-3
s = 15
for quadfun in [QuadOsc, EvansWebster]: # , AdaptiveLevin]:
quad = quadfun(f, g, dg, a, b, s=s, endpoints=False,
full_output=True)
val, _info = quad(omega)
assert_allclose(val.real, true_val)
s = 1 if s <= 2 else s // 2
# self.assert_(info.error_estimate < 1e-10)
# assert_allclose(info.n, 11)
def test_I9_exp_tant_sec2t_exp_jw_tant(self):
a = 0
b = np.pi/2
omega = 100
def f(t):
return np.exp(-np.tan(t))/np.cos(t)**2
def g(t):
return np.tan(t)
def dg(t):
return 1./np.cos(t)**2
true_val = (0.0000999900009999000099990000999900009999000099990000999 +
0.009999000099990000999900009999000099990000999900009999j)
for quadfun in [QuadOsc, EvansWebster, AdaptiveLevin]:
quad = quadfun(f, g, dg, a, b, endpoints=False, full_output=True)
val, info = quad(omega)
assert_allclose(val, true_val)
self.assert_(info.error_estimate < 1e-8)
def test_exp_zdcos2t_dcos2t_exp_jw_cos_t_b_dcos2t(self):
x1 = -20
y1 = 20
z1 = 20
beta = np.abs(np.arctan(y1/x1))
R = np.sqrt(x1**2+y1**2)
def f(t, beta, z1):
cos2t = np.cos(t)**2
return np.where(cos2t == 0, 0, np.exp(-z1/cos2t)/cos2t)
def g(t, beta, z1):
return np.cos(t-beta)/np.cos(t)**2
def dg(t, beta, z1=0):
cos3t = np.cos(t)**3
return 0.5*(3*np.sin(beta)-np.sin(beta-2*t))/cos3t
def append_dg_zero(zeros, g1, beta):
signs = [1, ] if np.abs(g1) <= _EPS else [-1, 1]
for sgn1 in signs:
tn = np.arccos(sgn1 * g1)
if -np.pi / 2 <= tn <= np.pi / 2:
for sgn2 in [-1, 1]:
t = sgn2 * tn
if np.abs(dg(t, beta)) < 10*_EPS:
zeros.append(t)
return zeros
def zeros_dg(beta):
k0 = (9*np.cos(2*beta)-7)
if k0 < 0: # No stationary points
return ()
k1 = 3*np.cos(2*beta)-5
g0 = np.sqrt(2)*np.sqrt(np.cos(beta)**2*k0)
zeros = []
if g0+k1 < _EPS:
g1 = 1./2*np.sqrt(-g0-k1)
zeros = append_dg_zero(zeros, g1, beta)
if _EPS < g0-k1:
g2 = 1./2*np.sqrt(g0-k1)
zeros = append_dg_zero(zeros, g2, beta)
if np.abs(g0+k1) <= _EPS or np.abs(g0-k1) <= _EPS:
zeros = append_dg_zero(zeros, 0, beta)
return tuple(zeros)
a = -np.pi/2
b = np.pi/2
omega = R
def ftot(t):
cos2t = mp.cos(t)**2
return (mp.exp(-z1/cos2t) / cos2t *
mp.exp(1j * omega * mp.cos(t-beta)/cos2t))
zdg = zeros_dg(beta)
ab = (a, ) + zdg + (b, )
true_val, _err = mp.quadts(ftot, ab, maxdegree=9, error=True)
import matplotlib.pyplot as plt
t = np.linspace(a, b, 5*513)
plt.subplot(2, 1, 1)
f2 = f(t, beta, z1)*np.exp(1j*R*g(t, beta, z1))
true_val2 = np.trapz(f2, t)
plt.plot(t, f2.real, t, f2.imag, 'r')
plt.title('integral=%g+1j%g, '
'(%g+1j%g)' % (true_val2.real, true_val2.imag,
true_val.real, true_val.imag))
plt.subplot(2, 1, 2)
plt.plot(t, dg(t, beta, z1), 'r')
plt.plot(t, g(t, beta, z1))
plt.hlines(0, a, b)
plt.axis([a, b, -5, 5])
plt.title('beta=%g' % beta)
print(np.trapz(f2, t))
plt.show('hold')
# true_val = 0.00253186684281+0.004314054498j
# s = 15
for quadfun in [QuadOsc, EvansWebster, AdaptiveLevin]:
# EvansWebster]: # , AdaptiveLevin, ]:
quad = quadfun(f, g, dg, a, b, precision=10, endpoints=False,
full_output=True)
val, _info = quad(omega, beta, z1) # @UnusedVariable
# assert_allclose(val, complex(true_val), rtol=1e-3)
# s = 1 if s<=1 else s//2
pass
if __name__ == "__main__":
# import sys;sys.argv = ['', 'Test.testName']
unittest.main()

@ -475,64 +475,64 @@ def test_tranproc():
class TestPiecewise(TestCase):
def test_condition_is_single_bool_list(self):
assert_raises(ValueError, piecewise, [0, 0], [True, False], [1])
assert_raises(ValueError, piecewise, [True, False], [1], [0, 0])
def test_condition_is_list_of_single_bool_list(self):
x = piecewise([0, 0], [[True, False]], [1])
x = piecewise([[True, False]], [1], [0, 0])
assert_array_equal(x, [1, 0])
def test_conditions_is_list_of_single_bool_array(self):
x = piecewise([0, 0], [np.array([True, False])], [1])
x = piecewise([np.array([True, False])], [1], [0, 0])
assert_array_equal(x, [1, 0])
def test_condition_is_single_int_array(self):
assert_raises(ValueError, piecewise, [0, 0], np.array([1, 0]), [1])
assert_raises(ValueError, piecewise, np.array([1, 0]), [1], [0, 0])
def test_condition_is_list_of_single_int_array(self):
x = piecewise([0, 0], [np.array([1, 0])], [1])
x = piecewise([np.array([1, 0])], [1], [0, 0])
assert_array_equal(x, [1, 0])
def test_simple(self):
x = piecewise([0, 0], [[False, True]], [lambda x:-1])
x = piecewise([[False, True]], [lambda x:-1], [0, 0])
assert_array_equal(x, [0, -1])
x = piecewise([1, 2], [[True, False], [False, True]], [3, 4])
x = piecewise([[True, False], [False, True]], [3, 4], [1, 2])
assert_array_equal(x, [3, 4])
def test_default(self):
# No value specified for x[1], should be 0
x = piecewise([1, 2], [[True, False]], [2])
x = piecewise([[True, False]], [2], [1, 2],)
assert_array_equal(x, [2, 0])
# Should set x[1] to 3
x = piecewise([1, 2], [[True, False]], [2, 3])
x = piecewise([[True, False]], [2, 3], [1, 2])
assert_array_equal(x, [2, 3])
def test_0d(self):
x = np.array(3)
y = piecewise(x, [x > 3], [4, 0])
y = piecewise([x > 3], [4, 0], x)
assert_(y.ndim == 0)
assert_(y == 0)
x = 5
y = piecewise(x, [[True], [False]], [1, 0])
assert_(y.ndim == 0)
y = piecewise([[True], [False]], [1, 0], x)
assert_(y == 1)
assert_(y.ndim == 0)
def test_abs_function(self):
x = np.linspace(-2.5, 2.5, 6)
vals = piecewise((x,), [x < 0, x >= 0], [lambda x: -x, lambda x: x])
vals = piecewise([x < 0, x >= 0], [lambda x: -x, lambda x: x], (x,))
assert_array_equal(vals,
[2.5, 1.5, 0.5, 0.5, 1.5, 2.5])
def test_abs_function_with_scalar(self):
x = np.array(-2.5)
vals = piecewise((x,), [x < 0, x >= 0], [lambda x: -x, lambda x: x])
vals = piecewise([x < 0, x >= 0], [lambda x: -x, lambda x: x], (x,))
assert_(vals == 2.5)
def test_otherwise_condition(self):
x = np.linspace(-2.5, 2.5, 6)
vals = piecewise((x,), [x < 0, ], [lambda x: -x, lambda x: x])
vals = piecewise([x < 0, ], [lambda x: -x, lambda x: x], (x,))
assert_array_equal(vals, [2.5, 1.5, 0.5, 0.5, 1.5, 2.5])
def test_passing_further_args_to_fun(self):
@ -542,24 +542,24 @@ class TestPiecewise(TestCase):
def fun1(x, y, scale=1.):
return x*y/scale
x = np.linspace(-2.5, 2.5, 6)
vals = piecewise((x,), [x < 0, ], [fun0, fun1], args=(2.,), scale=2.)
vals = piecewise([x < 0, ], [fun0, fun1], (x,), args=(2.,), scale=2.)
assert_array_equal(vals, [2.5, 1.5, 0.5, 0.5, 1.5, 2.5])
def test_step_function(self):
x = np.linspace(-2.5, 2.5, 6)
vals = piecewise(x, [x < 0, x >= 0], [-1, 1])
vals = piecewise([x < 0, x >= 0], [-1, 1], x)
assert_array_equal(vals, [-1., -1., -1., 1., 1., 1.])
def test_step_function_with_scalar(self):
x = 1
vals = piecewise(x, [x < 0, x >= 0], [-1, 1])
vals = piecewise([x < 0, x >= 0], [-1, 1], x)
assert_(vals == 1)
def test_function_with_two_args(self):
x = np.linspace(-2, 2, 5)
X, Y = np.meshgrid(x, x)
vals = piecewise(
(X, Y), [X * Y < 0, ], [lambda x, y: -x * y, lambda x, y: x * y])
[X * Y < 0, ], [lambda x, y: -x * y, lambda x, y: x * y], (X, Y))
assert_array_equal(vals, [[4., 2., -0., 2., 4.],
[2., 1., -0., 1., 2.],
[-0., -0., 0., 0., 0.],
@ -569,8 +569,8 @@ class TestPiecewise(TestCase):
def test_fill_value_and_function_with_two_args(self):
x = np.linspace(-2, 2, 5)
X, Y = np.meshgrid(x, x)
vals = piecewise((X, Y), [X * Y < -0.5, X * Y > 0.5],
[lambda x, y: -x * y, lambda x, y: x * y],
vals = piecewise([X * Y < -0.5, X * Y > 0.5],
[lambda x, y: -x * y, lambda x, y: x * y], (X, Y),
fill_value=np.nan)
nan = np.nan
assert_array_equal(vals, [[4., 2., nan, 2., 4.],
@ -582,8 +582,8 @@ class TestPiecewise(TestCase):
def test_fill_value2_and_function_with_two_args(self):
x = np.linspace(-2, 2, 5)
X, Y = np.meshgrid(x, x)
vals = piecewise((X, Y), [X * Y < -0.5, X * Y > 0.5],
[lambda x, y: -x * y, lambda x, y: x * y, np.nan])
vals = piecewise([X * Y < -0.5, X * Y > 0.5],
[lambda x, y: -x * y, lambda x, y: x * y, np.nan], (X, Y))
nan = np.nan
assert_array_equal(vals, [[4., 2., nan, 2., 4.],
[2., 1., nan, 1., 2.],

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