change the bin countour function so it uses a PatchCollection instead…

… of plotting individual bins on the axis in a for loop

pygtm/physical.py

@@ -2,7 +2,8 @@
 import numpy as np
 import cartopy.crs as ccrs
 from cartopy.mpl.geoaxes import GeoAxes
-
+from matplotlib.patches import Rectangle
+from matplotlib.collections import PatchCollection
 
 class physical_space:
     def __init__(self, lon, lat, resolution):
@@ -140,31 +141,32 @@ def vector_to_matrix(self, vector):
         mat[self.id_og] = vector
         return np.ma.masked_invalid(mat.reshape((self.ny - 1, self.nx - 1)))
 
-    def bins_contour(self, ax, color='k', bin_id=None):
+    def bins_contour(self, ax, edgecolor='k', bin_id=None, projection=None):
         """
         Plot all element bins on one axis
         Args:
             ax: axis to plot on
-            color: bins contour color
+            edgecolor: bins contour color
             bin_id: which bins to plot (default all)
+            projection: add transform keyword to convert to cartopy projection
         """
         if bin_id is None:
             bins = self.bins
         else:
             bins = self.bins[bin_id]
 
+        patches = []
         for b_i in bins:
             # corners and width/height of element
             c = (self.coords[b_i[0]][0], self.coords[b_i[0]][1])
             w = self.coords[b_i[1]][0] - self.coords[b_i[0]][0]
             h = self.coords[b_i[2]][1] - self.coords[b_i[0]][1]
+            patches.append(Rectangle(c, w, h, edgecolor=edgecolor, fill=False, linewidth=0.5))
+
+        if projection is not None:
+            p = PatchCollection(patches, transform=projection, match_original=True)
+        else:
+            p = PatchCollection(patches, match_original=True)
 
-            if isinstance(ax, GeoAxes):
-                ax.plot([c[0], c[0] + w, c[0] + w, c[0], c[0]],
-                        [c[1], c[1], c[1] + h, c[1] + h, c[1]],
-                        color, linewidth=0.2, zorder=1, transform=ccrs.PlateCarree())
-            else:
-                ax.plot([c[0], c[0] + w, c[0] + w, c[0], c[0]],
-                        [c[1], c[1], c[1] + h, c[1] + h, c[1]],
-                        color, linewidth=0.2, zorder=1)
-        return
+        ax.add_collection(p)
+        return