Initial Commit

utils/visualize_tsp.py

@@ -0,0 +1,54 @@
+import matplotlib.pyplot as plt
+
+def plotTSP(paths, points, num_iters=1):
+
+    """
+    path: List of lists with the different orders in which the nodes are visited
+    points: coordinates for the different nodes
+    num_iters: number of paths that are in the path list
+
+    """
+
+    # Unpack the primary TSP path and transform it into a list of ordered
+    # coordinates
+
+    x = []; y = []
+    for i in paths[0]:
+        x.append(points[i][0])
+        y.append(points[i][1])
+
+    plt.plot(x, y, 'co')
+
+    # Set a scale for the arrow heads (there should be a reasonable default for this, WTF?)
+    # a_scale = float(max(x))/float(100)
+
+    # Draw the older paths, if provided
+    if num_iters > 1:
+
+        for i in range(1, num_iters):
+
+            # Transform the old paths into a list of coordinates
+            xi = []; yi = [];
+            for j in paths[i]:
+                xi.append(points[j][0])
+                yi.append(points[j][1])
+
+            plt.arrow(xi[-1], yi[-1], (xi[0] - xi[-1]), (yi[0] - yi[-1]), 
+                    color = 'r', length_includes_head = True, ls = 'dashed',
+                    width = 0.001/float(num_iters))
+            for i in range(0, len(x) - 1):
+                plt.arrow(xi[i], yi[i], (xi[i+1] - xi[i]), (yi[i+1] - yi[i]),
+                        color = 'r', length_includes_head = True,
+                        ls = 'dashed', width = 0.001/float(num_iters))
+
+    # Draw the primary path for the TSP problem
+    plt.arrow(x[-1], y[-1], (x[0] - x[-1]), (y[0] - y[-1]),
+            color ='g', length_includes_head=True)
+    for i in range(0,len(x)-1):
+        plt.arrow(x[i], y[i], (x[i+1] - x[i]), (y[i+1] - y[i]),
+                color = 'g', length_includes_head = True)
+
+    #Set axis too slitghtly larger than the set of x and y
+    # plt.xlim(min(x)*1.1, max(x)*1.1)
+    # plt.ylim(min(y)*1.1, max(y)*1.1)
+    plt.show()