matplotlib example bad map (snippet)

Python matplotlib example 'bad map'

Modules used in program:

import numpy as np
import matplotlib.patches as patches
import matplotlib.pyplot as plt
import matplotlib.cm as jimbo
import shapefile

python bad map

Python matplotlib example: bad map

""" I did not write this, though I fixed a syntax error in it. I just found it while looking for an easy way to plot a world choropleth map. It is probably the worst program I've ever seen and felt I should keep it for some reason. """ 

import shapefile
import matplotlib.cm as jimbo
import matplotlib.pyplot as plt
import matplotlib.patches as patches
from matplotlib.patches import Polygon
from matplotlib.collections import PatchCollection
import numpy as np

#   -- input --
sf = shapefile.Reader("ne_110m_admin_0_countries.shp")
recs    = sf.records()
shapes  = sf.shapes()
Nshp    = len(shapes)
cns     = []
for nshp in xrange(Nshp):
    cns.append(recs[nshp][1])
cns = np.array(cns)
cm    = jimbo.get_cmap('Dark2')
cccol = cm(1.*np.arange(Nshp)/Nshp)
#   -- plot --
fig     = plt.figure()
ax      = fig.add_subplot(111)
for nshp in xrange(Nshp):
    ptchs   = []
    pts     = np.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(-180,+180)
ax.set_ylim(-90,90)

#fig.savefig('test.png')
plt.show()

Python links

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