added histgrm + small bugfixes

pywafo/src/wafo/misc.py

@@ -14,6 +14,7 @@ from numpy import (abs, amax, any, logical_and, arange, linspace, atleast_1d,
 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):
     ''' 
@@ -1849,6 +1850,66 @@ 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)

pywafo/src/wafo/objects.py

@@ -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):