[Scipy-svn] r3373 - trunk/scipy/sandbox/dhuard

[scipy-svn@scip...]

Author: dhuard
Date: 2007-09-27 09:03:00 -0500 (Thu, 27 Sep 2007)
New Revision: 3373

Added:
   trunk/scipy/sandbox/dhuard/test_stats.py
Modified:
   trunk/scipy/sandbox/dhuard/stats.py
Log:
Added tests for stats stub.

Modified: trunk/scipy/sandbox/dhuard/stats.py
===================================================================
--- trunk/scipy/sandbox/dhuard/stats.py	2007-09-27 13:25:57 UTC (rev 3372)
+++ trunk/scipy/sandbox/dhuard/stats.py	2007-09-27 14:03:00 UTC (rev 3373)
@@ -1,32 +1,36 @@
 import scipy.interpolate as interpolate
 import numpy as np
 
-def scoreatpercentile(data, per):
-    """Return the score at the given 'per' percentile of the data.
+def scoreatpercentile(data, percentile):
+    """Return the score at the given percentile of the data.
     
-    Example
-    >>> scoreatpercentile(randn(100), 50)
-    will return the median of the sample.
+    Example:
+    	>>> data = randn(100)
+	    >>> scoreatpercentile(data, 50)
+    	
+    	will return the median of sample `data`.
     """
+    per = np.array(percentile)
     cdf = empiricalcdf(data)
-    interpolator = interpolate.interp1d(sort(cdf), sort(data))
+    interpolator = interpolate.interp1d(np.sort(cdf), np.sort(data))
     return interpolator(per/100.)
     
 def percentileofscore(data, score):
-    """Percentile-position of score relative to data.
+    """Return the percentile-position of score relative to data.
       
     score: Array of scores at which the percentile is computed.
     
     Return percentiles (0-100).
     
     Example
+	    r = randn(50)
         x = linspace(-2,2,100)
-        percentileofscore(randn(50),x)
+        percentileofscore(r,x)
         
-    Return an error if the score is outside the range of data. 
+    Raise an error if the score is outside the range of data. 
     """
     cdf = empiricalcdf(data)
-    interpolator = interpolate.interp1d(sort(data), sort(cdf))
+    interpolator = interpolate.interp1d(np.sort(data), np.sort(cdf))
     return interpolator(score)*100.
 
 def empiricalcdf(data, method='Hazen'):
@@ -46,11 +50,10 @@
     i = np.argsort(np.argsort(data)) + 1.
     N = len(data)
     method = method.lower()
-    
-    if method == 'weibull':
+    if method == 'hazen':
+        cdf = (i-0.5)/N
+    elif method == 'weibull':
         cdf = i/(N+1.)
-    elif method == 'hazen':
-        cdf = (i-0.5)/N
     elif method == 'california':
         cdf = (i-1.)/N
     elif method == 'chegodayev':

Added: trunk/scipy/sandbox/dhuard/test_stats.py
===================================================================
--- trunk/scipy/sandbox/dhuard/test_stats.py	2007-09-27 13:25:57 UTC (rev 3372)
+++ trunk/scipy/sandbox/dhuard/test_stats.py	2007-09-27 14:03:00 UTC (rev 3373)
@@ -0,0 +1,45 @@
+"""
+Test statistical functions.
+"""
+
+
+from numpy.testing import *
+import stats
+import numpy as np
+
+N = 100
+np.random.seed(2)
+r = np.random.randn(N)
+
+class test_empiricalcdf(NumpyTestCase):
+	def check_hazen(self):
+		
+		f = stats.empiricalcdf(r)
+		assert_equal(len(f), len(r))
+		assert_array_equal(np.argsort(r), np.argsort(f))
+		assert_array_equal(np.sort(f), (np.arange(N)+.5)/N) 
+		
+	def check_weibull(self):
+		f = stats.empiricalcdf(r, 'weibull')
+		assert_array_equal(np.sort(f), (np.arange(N)+1.)/(N+1.))
+
+	def check_california(self):
+		f = stats.empiricalcdf(r, 'california')
+		assert_array_equal(np.sort(f), (np.arange(N))/float(N))
+		
+class test_scoreatpercentile(NumpyTestCase):
+	def check_simple(self):
+		r = np.random.randn(1000)
+		s = stats.scoreatpercentile(r, [15.9,50,84.1])
+		assert_array_almost_equal(s, [-1,0,1], 1)
+		
+class test_percentileofscore(NumpyTestCase):
+	def check_simple(self):
+		r = np.random.randn(3000)
+		p = stats.percentileofscore(r, [-1,0,1])
+		assert_array_almost_equal(p, [15.9, 50, 84.1], 0)
+		
+		
+		
+if __name__ == '__main__':
+	NumpyTest().run()