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I want to plot the Canadian shapefile with province boundaries highlighted and hollow filling.

I have downloaded the shapefile from here.

This is the script I use to visualize the shapefile:

import shapefile
import matplotlib.pyplot as plt
import matplotlib.patches as patches
from matplotlib.patches import Polygon
from matplotlib.collections import PatchCollection
#   -- input --
sf = shapefile.Reader("myfolder\gpr_000a11a_e.shp")
recs    = sf.records()
shapes  = sf.shapes()
Nshp    = len(shapes)
cns     = []
for nshp in xrange(Nshp):
    cns.append(recs[nshp][1])
cns = array(cns)
cm    = get_cmap('Dark2')
cccol = cm(1.*arange(Nshp)/Nshp)
#   -- plot --
fig     = plt.figure()
ax      = fig.add_subplot(111)
for nshp in xrange(Nshp):
    ptchs   = []
    pts     = array(shapes[nshp].points)
    prt     = shapes[nshp].parts
    par     = list(prt) + [pts.shape[0]]
    for pij in xrange(len(prt)):
     ptchs.append(Polygon(pts[par[pij]:par[pij+1]]))
    ax.add_collection(PatchCollection(ptchs,facecolor=cccol[nshp,:],edgecolor='k', linewidths=.1))
ax.set_xlim(-160,-40)
ax.set_ylim(40,90)

The output is confusing, in that the Northern border is completely wrong and it does not resemble the real one. I think there are unwanted lines that connect points far away from each other. As a result, the islands in Northern Nunavut have been merged in a single polygon. How to obtain a neat border?

enter image description here

3

The polygon is not "wrong", it's just not representing landmass enter image description here

It uses 1 polygon for each province.

You can find polygons representing Canada's borders and land surface on GADM or DIVA-GIS

  • And do you know where I can get a shapefile representing the true landmass? – FaCoffee Jun 21 '16 at 10:51
  • 1
    @CF84 I've just edited my answer, take a look at the links. you can always do a search for "Canada District Shapefile" and find plenty of results as well – HDunn Jun 21 '16 at 10:52

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