Changeset 4501

Timestamp:

May 28, 2007, 1:14:38 PM (18 years ago)

Author:

nick

Message:

fixed split function to run quicker and use less memory

Location:

anuga_core/source/anuga/geospatial_data

Files:

• geospatial_data.py (modified) (4 diffs)
• test_geospatial_data.py (modified) (3 diffs)

anuga_core/source/anuga/geospatial_data/geospatial_data.py

@@ -10 +10 @@
 from Numeric import concatenate, array, Float, shape, reshape, ravel, take, \
                         size, shape
-from random import randint
+#from Array import tolist
+from RandomArray import randint
 from copy import deepcopy
 
@@ -675 +676 @@
     
     def split(self, factor=0.5, verbose=False):
-        """Returns two geospatial_data object, first is size of the 'factor'
-        smaller the original and the second is the remainer. The two new 
+        """Returns two geospatial_data object, first is the size of the 'factor'
+        smaller the original and the second is the remainder. The two new 
         object are disjoin set of each other. 
         
@@ -682 +683 @@
         AND if factor is a decimal it will round (2.25 to 2 and 2.5 to 3)
         
-        
+        This method create two lists of indices which are passed into get_sample.
+        The lists are created using random numbers, and they are unique sets eg.
+        total_list(1,2,3,4,5,6,7,8,9)  random_list(1,3,6,7,9) and remainder_list(0,2,4,5,8)
+                
         Input - the factor which to split the object, if 0.1 then 10% of the
             object will be returned
@@ -695 +699 @@
         remainder_list = []
         new_size = round(factor*self_size)
-   #     print'Split original %s by %s' %(self_size, factor)
-   #     print'New samples are %s and %s in size' %(int(round(factor*self_size)),int(self_size-new_size))
         
         #find unique random numbers
         if verbose: print "make unique random number list and get indices"
-        while i < new_size:
-            random_num = randint(0,self_size-1)
-            if random_num not in random_list:
-                random_list.append(random_num)
-                i=i+1
-
-        #Make list of opposite to random_list
-        if verbose: print "make list of opposite to random list"
-        for i in range(0,self_size,1):
-            remainder_list.append(i)
-
-        #remove random list from remainder_list to get correct remainder_list
+
+        total=array(range(self_size))
+        total_list = total.tolist()
+        if verbose: print "total list len",len(total_list)
+                
+        #there will be repeated random numbers however will not be a 
+        #problem as they are being 'pop'ed out of array so if there
+        #are two numbers the same they will pop different indicies, 
+        #still basically random
+        ## create list of non-unquie random numbers
+        if verbose: print "create random numbers list %s long" %new_size
+        random_num = randint(0,self_size-1,(int(new_size),))
+        random_num = random_num.tolist()
+
         #need to sort and reverse so the pop() works correctly
-        random_list.sort()
-        random_list.reverse()
-        if verbose: print "get indices of opposite to random list"
-        for i in random_list:
-            remainder_list.pop(i)
-            if verbose:
-                if ((i/100)==(float(i)/100)): print "reached: ",i
-            
+        random_num.sort()
+        random_num.reverse()        
+        
+        if verbose: print "make random number list and get indices"
+        j=0
+        k=1
+        remainder_list = total_list[:]
+        #pops array index (random_num) from remainder_list (which starts as the 
+        #total_list and appends to random_list  
+        random_num_len = len(random_num)
+        for i in random_num:
+            random_list.append(remainder_list.pop(i))
+            j+=1
+            #prints progress
+            if verbose and round(random_num_len/10*k)==j:
+                print '(%s/%s)' %(j, random_num_len)
+                k+=1
+        
+        #FIXME: move to tests, it might take a long time
+        #then create an array of random lenght between 500 and 1000, 
+        #and use a random factor between 0 and 1 
+        #setup for assertion
+        test_total = random_list[:]
+        test_total.extend(remainder_list)
+        test_total.sort() 
+        msg = 'The two random lists made from the original list when added together '\
+         'DO NOT equal the original list'
+        assert (total_list==test_total),msg
+
         #get new samples
         if verbose: print "get values of indices for random list"

anuga_core/source/anuga/geospatial_data/test_geospatial_data.py

@@ -4 +4 @@
 import unittest
 import os
-from Numeric import zeros, array, allclose, concatenate
+from Numeric import zeros, array, allclose, concatenate,sort
 from math import sqrt, pi
 import tempfile
@@ -2232 +2232 @@
                       14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25]}
         G = Geospatial_data(points, attributes)
-#        print G.get_data_points()
-#        print G.get_attributes()
 
         factor = 0.21
@@ -2240 +2238 @@
         G1, G2  = G.split(factor) 
         
-#        print 'len(G): %s len(G1): %s len(G2): %s' %(len(G), len(G1), len(G2))
-#        print 'G: ', len(G),'G1: ', len(G1), 'G2: ', len(G2)
-
         assert allclose(len(G), len(G1)+len(G2))
         assert allclose(round(len(G)*factor), len(G1))
         
-#        assert allclose(G == G1 + G2) must implentent __equal__
+#        assert allclose(G, G1+G2)# must implentent __equal__ or a sort