Merge branch 'master' into dev3

Author: weilycoder

.pylintrc

@@ -0,0 +1,2 @@
+[MASTER]
+py-version=3.5

cyaron/__init__.py

@@ -5,17 +5,19 @@
 """
 
 from __future__ import absolute_import
+
+from random import choice, randint, random, randrange, uniform
+
+#from .visual import visualize
+from . import log
+from .compare import Compare
+from .consts import *
+from .graph import Edge, Graph
 from .io import IO
-from .graph import Graph, Edge
-from .string import String
+from .math import *
+from .merger import Merger
+from .polygon import Polygon
 from .sequence import Sequence
+from .string import String
 from .utils import *
-from .consts import *
 from .vector import Vector
-from .polygon import Polygon
-from .compare import Compare
-from .math import *
-from .merger import Merger
-#from .visual import visualize
-from . import log
-from random import randint, randrange, uniform, choice, random

cyaron/graph.py

@@ -39,6 +39,15 @@ def __init__(self, point_count, directed=False):
         """
         self.directed = directed
         self.edges = [[] for i in range(point_count + 1)]
+    
+    def edge_count(self):
+        """edge_count(self) -> int
+            Return the count of the edges in the graph.
+        """
+        cnt = sum(len(node) for node in self.edges)
+        if not self.directed:
+            cnt //= 2
+        return cnt
 
     def to_str(self, **kwargs):
         """to_str(self, **kwargs) -> str
@@ -260,6 +269,11 @@ def graph(point_count, edge_count, **kwargs):
         directed = kwargs.get("directed", False)
         self_loop = kwargs.get("self_loop", True)
         repeated_edges = kwargs.get("repeated_edges", True)
+        if not repeated_edges:
+            max_edge =  Graph._calc_max_edge(point_count, directed, self_loop)
+            if edge_count > max_edge:
+                raise Exception("the number of edges of this kind of graph which has %d vertexes must be less than or equal to %d." % (point_count, max_edge))
+
         weight_limit = kwargs.get("weight_limit", (1, 1))
         if not list_like(weight_limit):
             weight_limit = (1, weight_limit)
@@ -309,6 +323,11 @@ def DAG(point_count, edge_count, **kwargs):
         self_loop = kwargs.get("self_loop", False) # DAG default has no loop
         repeated_edges = kwargs.get("repeated_edges", True)
         loop = kwargs.get("loop", False)
+        if not repeated_edges:
+            max_edge =  Graph._calc_max_edge(point_count, not loop, self_loop)
+            if edge_count > max_edge:
+                raise Exception("the number of edges of this kind of graph which has %d vertexes must be less than or equal to %d." % (point_count, max_edge))
+
         weight_limit = kwargs.get("weight_limit", (1, 1))
         if not list_like(weight_limit):
             weight_limit = (1, weight_limit)
@@ -369,6 +388,11 @@ def UDAG(point_count, edge_count, **kwargs):
 
         self_loop = kwargs.get("self_loop", True)
         repeated_edges = kwargs.get("repeated_edges", True)
+        if not repeated_edges:
+            max_edge =  Graph._calc_max_edge(point_count, False, self_loop)
+            if edge_count > max_edge:
+                raise Exception("the number of edges of this kind of graph which has %d vertexes must be less than or equal to %d." % (point_count, max_edge))
+
         weight_limit = kwargs.get("weight_limit", (1, 1))
         if not list_like(weight_limit):
             weight_limit = (1, weight_limit)
@@ -450,3 +474,12 @@ def hack_spfa(point_count, **kwargs):
             graph.add_edge(u, v, weight=weight_gen())
 
         return graph
+    
+    @staticmethod
+    def _calc_max_edge(point_count, directed, self_loop):
+        max_edge = point_count * (point_count - 1)
+        if not directed:
+            max_edge //= 2
+        if self_loop:
+            max_edge += point_count
+        return max_edge