fixed bug that win was not recognized when we had 5 or more in a row

Author: gosom

README.md

@@ -53,3 +53,4 @@ About the negamax algorithm here: http://www.hamedahmadi.com/gametree/#negamax
     Giorgos Komninos
     Alexandr Sapunji
     Stephen Gunashekar
+    Shubham Agarwal

tictac/lib/gamestate.py

@@ -6,6 +6,7 @@
 from copy import copy, deepcopy
 import itertools
 import math
+import operator
 
 import numpy as np
 
@@ -104,6 +105,9 @@ def winner(self):
         return None
 
     def evaluation(self):
+        """Returns 0 if we have a draw.
+        If we have a winner returns the winner (1 | -1)
+        else if there are still available moves returns 100"""
         if self.winner in (-1, 1):
             return self.winner
         if self.move_still_possible():
@@ -116,7 +120,6 @@ def move_still_possible(self):
         if there is no game then the sum of the absolute values
         of all elements should be  ndarray.size
         """
-        #print self.gameState.sum()
         return np.absolute(self.gameState).sum() < self.gameState.size
 
     def get_available_moves(self):
@@ -144,11 +147,8 @@ def do_move(self, move, player):
     def is_win(self, p):
         """Determine if the player has a 4 in a row in:
             - columns, rows, diagonals
-            http://docs.scipy.org/doc/numpy/reference/generated/numpy.diag.html
         """
         assert p != 0
-        # fist for rows:
-        #rows_array = np.array_split(self.gameState, 6, axis=0)
         rows =  [self.gameState[i,:].tolist() for i in xrange(0, 6)]
         columns = [self.gameState[:,i].tolist() for i in xrange(0, 7)]
         diags = self.get_diagonals()
@@ -157,19 +157,36 @@ def is_win(self, p):
         return False
 
     def find_score4(self, l, p):
+        """Returns True if the l contains 4 in a row"""
+        comp_operator = operator.ge if p == 1 else operator.le
         for r in l:
             for k, v in itertools.groupby(r):
-                if sum(v) == p * 4:
+                if comp_operator(sum(v), p *4):
                     return True
         return False
 
     def get_diagonals(self):
-        """"""
+        """
+        Returns a list of all* the diagonals of the array.
+        * Actually we do not return the ones with len()<4 since
+        there we cannot have a score4 there.
+
+        Idea modified from here:
+        http://stackoverflow.com/questions/6313308/get-all-the-diagonals-in-a-matrix-list-of-lists-in-python
+
+        we want lower-left-to-upper-right and upper-left-to-lower right
+        diagonals.
+        "::-1" returns the rows in reverse. ":" returns the columns as is,
+        effectively vertically mirroring the original array so the wanted
+        diagonals are# lower-right-to-uppper-left.
+        ::-1 -> returns rows reversed.
+
+        """
         # upper diagonals k > 0
         diags = [self.gameState[::-1,:].diagonal(i)
                 for i in range(-6, 7)]
         diags.extend(self.gameState.diagonal(i) for i in range(6,-6,-1))
-        return list(d.tolist() for d in diags)
+        return filter(lambda e: len(e) > 3, [d.tolist() for d in diags])
 
 
 

tictac/lib/player.py

@@ -29,6 +29,8 @@ def opponent(self):
 class RandomPlayer(BasePlayer):
 
     def get_move(self, gs):
+        """
+        :gs : gameState object """
         return gs.get_random_move()
 
 

tictac/test/test_gamestate.py

@@ -87,11 +87,18 @@ def test_winner():
     assert gs.is_win(1) == False
     assert gs.is_win(-1) == True
     assert gs.winner == -1
+    gs = Connect4GameState(gs=np.zeros((6, 7), dtype=int),)
+    for i in xrange(0, 5):
+        gs.do_move(i, 1)
+    print gs
+    assert gs.is_win(1) == True
+
+
 
 def test_diagonals():
     gs = Connect4GameState(gs=np.zeros((6, 7), dtype=int),)
     gs.do_move(0, 1)
     gs.do_move(5, 1)
     gs.do_move(6, 1)
-    assert len(gs.get_diagonals()) == 25
+    assert len(gs.get_diagonals()) == 12