Add the RouteFinding Part 0 assignment files.

RouteFinding/node.py

@@ -0,0 +1,66 @@
+
+'''Node.py: This class implements simple node object and associated methods.
+ Nodes are created by passing in an x,y cartesian location for the node.  Node labels are created
+ by just assigning letters to nodes in ascending ASCII order; current index is kept as class variable
+ to ensure that each new node has a unique label.
+ The most interesting  internal method here is makeLabel, which generates unique labels.  We want easy to read
+ alpha labels...so it basically counts up in Base26, generating the corresponding ASCII labels.  Tricky!
+ '''
+
+__author__ = "Eck Doerry"
+__copyright__ = "Copyright 2018, Northern Arizona University, Flagstaff AZ"
+
+import scipy.spatial as graph
+import numpy as np
+
+class Node:
+
+# CLASS VAR:  curIndex is used to make sure that all nodes have a unique label.  Incremented every time a new
+#  node is generated.
+    curIndex=1
+
+    # CLASS METHOD.  Allows for reseting the index counter for generating new nodes. Used only for debugging!
+    def reset(cls):
+        cls.curIndex=1
+
+    # Create a new node at point x-y.  Optionally pass in a label for the node.  If no explicit label is passed
+    # in (which is usually the case), it auto-generates the next label in a sequences starting with A-Z, then
+    # going to AA, AB, AC, etc.
+    def __init__(self,newX,newY, newLabel= '*'):
+        self.x=newX
+        self.y=newY
+        if newLabel=='*':
+            self.label=self.makeLabel()
+        else:
+            self.label=newLabel
+
+    # Makes an upper case label starting at 'A'.  If >26 nodes, goes to 'AB', 'AC', etc.
+    # Works by basically counting in Base26:  converts the index into strings in Base26!
+    def makeLabel(self):
+        index=self.curIndex
+        out = []
+        while index>25:
+            out.append(index % 26)
+            index = int(index / 26)
+
+        out.append(index-1)
+        out.reverse()
+        Node.curIndex +=1
+        return "".join([chr(65+x) for x in out])
+
+
+    # Distance:  returns the cartesian distance between this node some other node that is passed in.
+    def distance(self,aNode):
+        return graph.distance.euclidean([self.x,self.y],[aNode.x,aNode.y])
+
+    def get(self):
+        return ([self.x,self.y],self.label)
+
+
+
+# Unit tests
+# x=Node(4,5)
+# y=Node(1,2)
+# print(x.get())
+# print(y.get())
+