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added histgrm + small bugfixes

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master
per.andreas.brodtkorb 14 years ago
parent 813a7c7b24
commit 0570d84923
2 changed files with 87 additions and 26 deletions
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103
pywafo/src/wafo/misc.py
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@ -7,13 +7,14 @@ import sys
import numpy as np
from numpy import (abs, amax, any, logical_and, arange, linspace, atleast_1d,
array, asarray, broadcast_arrays, ceil, floor, frexp, hypot,
array, asarray, broadcast_arrays, ceil, floor, frexp, hypot,
sqrt, arctan2, sin, cos, exp, log, mod, diff, empty_like,
finfo, inf, pi, interp, isnan, isscalar, zeros, ones,
r_, sign, unique, hstack, vstack, nonzero, where, extract)
from scipy.special import gammaln
import types
import warnings
from wafo import plotbackend
try:
import wafo.c_library as clib
@ -26,7 +27,7 @@ __all__ = ['JITImport', 'DotDict', 'Bunch', 'printf', 'sub_dict_select',
'parse_kwargs', 'ecross', 'findtc', 'findtp', 'findcross',
'findextrema', 'findrfc', 'rfcfilter', 'common_shape', 'argsreduce',
'stirlerr', 'getshipchar', 'betaloge', 'gravity', 'nextpow2',
'discretize', 'pol2cart', 'cart2pol', 'ndgrid', 'meshgrid']
'discretize', 'pol2cart', 'cart2pol', 'ndgrid', 'meshgrid', 'histgrm']
class JITImport(object):
'''
@ -246,7 +247,7 @@ def _findcross(xn):
n = len(xn)
iz, = (xn == 0).nonzero()
if len(iz)>0:
if len(iz) > 0:
# Trick to avoid turning points on the crossinglevel.
if iz[0] == 0:
if len(iz) == n:
@ -254,15 +255,15 @@ def _findcross(xn):
return zeros(0, dtype=np.int)
diz = diff(iz)
if len(diz)>0 and (diz>1).any():
if len(diz) > 0 and (diz > 1).any():
ix = iz[(diz > 1).argmax()]
else:
ix = iz[-1]
#x(ix) is a up crossing if x(1:ix) = v and x(ix+1) > v.
#x(ix) is a downcrossing if x(1:ix) = v and x(ix+1) < v.
xn[0:ix+1] = -xn[ix + 1]
iz = iz[ix+1::]
xn[0:ix + 1] = -xn[ix + 1]
iz = iz[ix + 1::]
for ix in iz.tolist():
xn[ix] = xn[ix - 1]
@ -1400,7 +1401,7 @@ def discretize(fun, a, b, tol=0.005, n=5):
err = 0.5 * amax(abs((y00 - y) / (abs(y00 + y) + tiny)))
return x, y
def discretize2(fun, a,b,tol=0.005, n=5):
def discretize2(fun, a, b, tol=0.005, n=5):
'''
Automatic adaptive discretization of function
@ -1432,23 +1433,23 @@ def discretize2(fun, a,b,tol=0.005, n=5):
'''
tiny = floatinfo.tiny
n += (mod(n,2)==0) # make sure n is odd
n += (mod(n, 2) == 0) # make sure n is odd
x = linspace(a, b, n)
fx = fun(x)
n2 = (n-1)/2
erri = hstack( (zeros((n2,1)), ones((n2,1)) )).ravel()
n2 = (n - 1) / 2
erri = hstack((zeros((n2, 1)), ones((n2, 1)))).ravel()
err = erri.max()
err0 = inf
#while (err != err0 and err > tol and n < nmax):
for j in range(50):
if err!=err0 and np.any(erri > tol):
if err != err0 and np.any(erri > tol):
err0 = err
# find top errors
I, = where(erri>tol)
I, = where(erri > tol)
# double the sample rate in intervals with the most error
y = (vstack(((x[I]+x[I-1])/2, (x[I+1]+x[I])/2)).T).ravel()
y = (vstack(((x[I] + x[I - 1]) / 2, (x[I + 1] + x[I]) / 2)).T).ravel()
fy = fun(y)
fy0 = interp(y, x, fx)
@ -1456,12 +1457,12 @@ def discretize2(fun, a,b,tol=0.005, n=5):
err = erri.max()
x = hstack((x,y))
x = hstack((x, y))
I = x.argsort()
x = x[I]
erri = hstack((zeros(len(fx)),erri))[I]
fx = hstack((fx,fy))[I]
erri = hstack((zeros(len(fx)), erri))[I]
fx = hstack((fx, fy))[I]
else:
break
@ -1488,7 +1489,7 @@ def pol2cart(theta, rho, z=None):
if z is None:
return x, y
else:
return x,y,z
return x, y, z
def cart2pol(x, y, z=None):
@ -1507,7 +1508,7 @@ def cart2pol(x, y, z=None):
'''
t, r = arctan2(y, x), hypot(x, y)
if z is None:
return t,r
return t, r
else:
return t, r, z
@ -1849,9 +1850,69 @@ def tranproc(x, f, x0, *xi):
warnings.warn('Transformation of derivatives of order>4 not supported.')
return y #y0,y1,y2,y3,y4
def histgrm(data, n=None, odd=False, scale=False, lintype='b-'):
'''HISTGRM Plot histogram
CALL: binwidth = histgrm(x,N,odd,scale)
binwidth = the width of each bin
Parameters
-----------
x = the data
n = approximate number of bins wanted
(default depending on length(x))
odd = placement of bins (0 or 1) (default 0)
scale = argument for scaling (default 0)
scale = 1 yields the area 1 under the histogram
lintype : specify color and lintype, see PLOT for possibilities.
Example:
R=rndgumb(2,2,1,100);
histgrm(R,20,0,1)
hold on
x=linspace(-3,16,200);
plot(x,pdfgumb(x,2,2),'r')
hold off
'''
x = np.atleast_1d(data)
if n is None:
n = np.ceil(4 * np.sqrt(np.sqrt(len(x))))
mn = x.min()
mx = x.max()
d = (mx - mn) / n * 2
e = np.floor(np.log(d) / np.log(10));
m = np.floor(d / 10 ** e)
if m > 5:
m = 5
elif m > 2:
m = 2
d = m * 10 ** e
mn = (np.floor(mn / d) - 1) * d - odd * d / 2
mx = (np.ceil(mx / d) + 1) * d + odd * d / 2
limits = np.arange(mn, mx, d)
bin, limits = np.histogram(data, bins=limits, normed=scale) #, new=True)
limits.shape = (-1, 1)
xx = limits.repeat(3, axis=1)
xx.shape = (-1,)
xx = xx[1:-1]
bin.shape = (-1, 1)
yy = bin.repeat(3, axis=1)
#yy[0,0] = 0.0 # pdf
yy[:, 0] = 0.0 # histogram
yy.shape = (-1,)
yy = np.hstack((yy, 0.0))
plotbackend.plotbackend.plot(xx, yy, lintype, limits, limits * 0)
binwidth = d
return binwidth
def _test_find_cross():
t = findcross([0, 0, 1, -1, 1],0)
t = findcross([0, 0, 1, -1, 1], 0)
def _test_common_shape():
@ -1936,8 +1997,8 @@ def _test_discretize():
def _test_discretize2():
import numpy as np
import pylab as plb
x,y = discretize2(np.cos,0,np.pi)
t = plb.plot(x,y)
x, y = discretize2(np.cos, 0, np.pi)
t = plb.plot(x, y)
plb.show()
plb.close('all')

2
pywafo/src/wafo/objects.py
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@ -895,7 +895,7 @@ class TimeSeries(WafoData):
"""
fs = 1. / (2 * self.sampling_period())
S, f = psd(self.data.ravel(), Fs=fs, *args, **kwargs)
fact = 2.0 * pi
fact = 2 * 2.0 * pi
w = fact * f
return _wafospec.SpecData1D(S / fact, w)
def trdata(self, method='nonlinear', **options):

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