Define function `in_window`

Put existing code into new function `in_window` because we also want
to use it in another script: `plot_traj.py`.

Analysis/plot_eddy_contours.py

@@ -28,6 +28,13 @@ from os import path
 from matplotlib import animation, patches
 import f90nml
 
+def in_window(point, window):
+    llcrnrlon, llcrnrlat, urcrnrlon, urcrnrlat = window
+    longit = point[0] + math.ceil((llcrnrlon - point[0]) / 360) * 360
+    # (in [llcrnrlon, llcrnrlon + 2 pi[)
+
+    return longit <= urcrnrlon and llcrnrlat <= point[1] <= urcrnrlat
+
 def select_ishapes(k, k1, ishape_last, reader_extr, window = None):
     """Select ishapes at date k and in window."""
     
@@ -47,12 +54,7 @@ def select_ishapes(k, k1, ishape_last, reader_extr, window = None):
         for ishape in range(ishape_first, ishape_last[k - k1] + 1):
             shape_rec_extr = reader_extr.shapeRecord(ishape)
             points = shape_rec_extr.shape.points[0]
-            llcrnrlon, llcrnrlat, urcrnrlon, urcrnrlat = window
-            points[0] += math.ceil((llcrnrlon - points[0]) / 360) * 360
-            # (in [llcrnrlon, llcrnrlon + 2 pi[)
-
-            if points[0] <= urcrnrlon and llcrnrlat <= points[1] <= urcrnrlat:
-                ishape_list.append(ishape)
+            if in_window(points, window): ishape_list.append(ishape)
 
     return ishape_list