test.py

from __future__ import (absolute_import, division, print_function)

# exercise all the projections by plotting
# etopo bathymetry/topography over them, plus
# drawing coastlines, state and
# country boundaries, filling continents and drawing
# parallels/meridians

frommpl_toolkits.basemapimportBasemap, cm, shiftgrid
importnumpyasnp
importmatplotlib.pyplotasplt
importmatplotlib.colorsascolors

cmap=cm.GMT_haxby# colormap to use

# read in topo data (on a regular lat/lon grid)
# longitudes go from 20 to 380.
topodat=np.loadtxt('etopo20data.gz')
lons=np.loadtxt('etopo20lons.gz')
lats=np.loadtxt('etopo20lats.gz')
lons, lats=np.meshgrid(lons, lats)

print('min/max etopo20 data:')
print(topodat.min(),topodat.max())

# create new figure
fig=plt.figure()
# setup cylindrical equidistant map projection (global domain).
m=Basemap(llcrnrlon=-180.,llcrnrlat=-90,urcrnrlon=180.,urcrnrlat=90.,\
resolution='c',area_thresh=10000.,projection='cyl')
# plot image over map.
im=m.pcolormesh(lons,lats,topodat,cmap=cmap,latlon=True)
m.colorbar() # draw colorbar
m.drawcoastlines()
# draw parallels
m.drawparallels(np.arange(-90,90,30),labels=[1,0,0,1])
# draw meridians
m.drawmeridians(np.arange(0,360,60),labels=[1,0,0,1])
plt.title('Cylindrical Equidistant')
print('plotting Cylindrical Equidistant example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup miller cylindrical map projection.
m=Basemap(llcrnrlon=-180.,llcrnrlat=-90,urcrnrlon=180.,urcrnrlat=90.,\
resolution='c',area_thresh=10000.,projection='mill')
# plot image over map.
im=m.pcolormesh(lons,lats,topodat,cmap=cmap,latlon=True)
m.colorbar(location='bottom',pad='7%') # draw colorbar
m.drawcoastlines() # draw coastlines
# draw parallels and meridiands
m.drawparallels(np.arange(-90,90,30),labels=[1,0,0,1])
m.drawmeridians(np.arange(0,360,60),labels=[1,0,0,1])
plt.title('Miller Cylindrical')
print('plotting Miller Cylindrical example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup gall stereographic cylindrical map projection.
m=Basemap(llcrnrlon=-180.,llcrnrlat=-90,urcrnrlon=180.,urcrnrlat=90.,\
resolution='c',area_thresh=10000.,projection='gall')
# plot image over map.
im=m.pcolormesh(lons,lats,topodat,cmap=cmap,latlon=True)
cb=m.colorbar() # draw colorbar
m.drawcoastlines() # draw coastlines
# draw parallels and meridiands
m.drawparallels(np.arange(-90,90,30),labels=[1,0,0,1])
m.drawmeridians(np.arange(0,360,60),labels=[1,0,0,1])
plt.title('Gall Stereographic Cylindrical',y=1.1)
print('plotting Gall Stereographic Cylindrical example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup cylindrical equal area map projection.
m=Basemap(llcrnrlon=-180.,llcrnrlat=-90,urcrnrlon=180.,urcrnrlat=90.,\
resolution='c',area_thresh=10000.,lat_ts=30,projection='cea')
# plot image over map.
im=m.pcolormesh(lons,lats,topodat,cmap=cmap,latlon=True)
cb=m.colorbar() # draw colorbar
m.drawcoastlines() # draw coastlines
# draw parallels and meridiands
m.drawparallels(np.arange(-90,90,30),labels=[1,0,0,1])
m.drawmeridians(np.arange(0,360,60),labels=[1,0,0,1])
plt.title('Cylindrical Equal Area',y=1.1)
print('plotting Cylindrical Equal Area example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup mercator map projection (-80 to +80).
m=Basemap(llcrnrlon=-180.,llcrnrlat=-75,urcrnrlon=180.,urcrnrlat=75.,\
resolution='c',area_thresh=10000.,projection='merc',lat_ts=20)
# plot image over map.
im=m.pcolormesh(lons,lats,topodat,cmap=cmap,latlon=True)
cb=m.colorbar() # draw colorbar
m.drawcoastlines() # draw coastlines
m.drawstates() # draw state boundaries
m.fillcontinents() # fill continents
# draw parallels and meridiands
m.drawparallels(np.arange(-90,90,30),labels=[1,0,0,1])
m.drawmeridians(np.arange(0,360,60),labels=[1,0,0,1])
plt.title('Mercator',y=1.1)
print('plotting Mercator example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup cassini-soldner basemap.
m=Basemap(llcrnrlon=-6,llcrnrlat=49,urcrnrlon=4,urcrnrlat=59,\
resolution='l',area_thresh=1000.,projection='cass',\
lat_0=54.,lon_0=-2.)
# plot image over map.
# transform to nx x ny regularly spaced native projection grid
nx=int((m.xmax-m.xmin)/20000.)+1; ny=int((m.ymax-m.ymin)/20000.)+1
# shift data so lons go from -180 to 180 instead of 20 to 380.
datamap,lonsmap=shiftgrid(180.,topodat,lons[0,:],start=False)
topomap=m.transform_scalar(datamap,lonsmap,lats[:,0],nx,ny)
# plot image over map.
im=m.imshow(topomap,cmap)
m.colorbar() # draw colorbar
m.drawcoastlines()
# draw parallels
delat=2.
circles=np.arange(40.,70.,delat)
m.drawparallels(circles,labels=[1,0,0,1],fontsize=10)
# draw meridians
delon=2.
meridians=np.arange(-10,10,delon)
m.drawmeridians(meridians,labels=[1,0,0,1],fontsize=10)
plt.title('Cassini-Soldner Projection')
print('plotting Cassini-Soldner example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup gnomonic basemap.
m=Basemap(llcrnrlon=-95.,llcrnrlat=-52,urcrnrlon=-35.,urcrnrlat=15.,\
resolution='c',area_thresh=10000.,projection='gnom',\
lat_0=-10.,lon_0=-60.)
cs=m.contourf(lons,lats,topodat,np.arange(-6500,5000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar() # draw colorbar
m.drawcoastlines()
m.drawcountries()
# draw parallels
delat=20.
circles=np.arange(-80.,100.,delat)
m.drawparallels(circles,labels=[1,0,0,1],fontsize=10)
# draw meridians
delon=20.
meridians=np.arange(-180,180,delon)
m.drawmeridians(meridians,labels=[1,0,0,1],fontsize=10)
plt.title('Gnomonic Projection')
print('plotting Gnomonic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup transverse mercator basemap.
m=Basemap(llcrnrlon=-6,llcrnrlat=49,urcrnrlon=4,urcrnrlat=59,\
resolution='l',area_thresh=1000.,projection='tmerc',\
lat_0=54.,lon_0=-2.)
# plot image over map.
# transform to nx x ny regularly spaced native projection grid
nx=int((m.xmax-m.xmin)/20000.)+1; ny=int((m.ymax-m.ymin)/20000.)+1
# shift data so lons go from -180 to 180 instead of 20 to 380.
datamap,lonsmap=shiftgrid(180.,topodat,lons[0,:],start=False)
topomap=m.transform_scalar(datamap,lonsmap,lats[:,0],nx,ny)
# plot image over map.
im=m.imshow(topomap,cmap)
m.colorbar() # draw colorbar
m.drawcoastlines()
# draw parallels
delat=2.
circles=np.arange(40.,70.,delat)
m.drawparallels(circles,labels=[1,0,0,1],fontsize=10)
# draw meridians
delon=2.
meridians=np.arange(-10,10,delon)
m.drawmeridians(meridians,labels=[1,0,0,1],fontsize=10)
plt.title('Transverse Mercator Projection')
print('plotting Transverse Mercator example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup oblique mercator basemap.
m=Basemap(height=16700000,width=12000000,
resolution='l',area_thresh=1000.,projection='omerc',\
lon_0=-100,lat_0=15,lon_2=-120,lat_2=65,lon_1=-50,lat_1=-55)
# plot image over map.
cs=m.contourf(lons,lats,topodat,np.arange(-6500,5000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar() # draw colorbar
m.drawcoastlines()
m.drawcountries()
m.drawstates()
# draw parallels
m.drawparallels(np.arange(-80,81,20),labels=[1,0,0,0],fontsize=10)
# draw meridians
m.drawmeridians(np.arange(-180,181,30),labels=[0,0,0,1],fontsize=10)
plt.title('Oblique Mercator Projection')
print('plotting Oblique Mercator example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup polyconic basemap.
m=Basemap(llcrnrlon=-35.,llcrnrlat=-30,urcrnrlon=80.,urcrnrlat=50.,\
resolution='c',area_thresh=1000.,projection='poly',\
lat_0=0.,lon_0=20.)
# plot image over map.
cs=m.contourf(lons,lats,topodat,np.arange(-6500,5000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar() # draw colorbar
m.drawcoastlines()
m.drawcountries()
# draw parallels
delat=20.
circles=np.arange(-80.,100.,delat)
m.drawparallels(circles,labels=[1,0,0,0],fontsize=10)
# draw meridians
delon=20.
meridians=np.arange(-180,180,delon)
m.drawmeridians(meridians,labels=[1,0,0,1],fontsize=10)
plt.title('Polyconic Projection')
print('plotting Polyconic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup equidistant conic
m=Basemap(llcrnrlon=-90.,llcrnrlat=18,urcrnrlon=-70.,urcrnrlat=26.,\
resolution='l',area_thresh=1000.,projection='eqdc',\
lat_1=21.,lat_2=23.,lon_0=-80.)
# plot image over map.
# transform to nx x ny regularly spaced native projection grid
nx=int((m.xmax-m.xmin)/20000.)+1; ny=int((m.ymax-m.ymin)/20000.)+1
# shift data so lons go from -180 to 180 instead of 20 to 380.
datamap,lonsmap=shiftgrid(180.,topodat,lons[0,:],start=False)
topomap=m.transform_scalar(datamap,lonsmap,lats[:,0],nx,ny)
# plot image over map.
im=m.imshow(topomap,cmap)
m.colorbar() # draw colorbar
m.drawcoastlines()
m.drawcountries()
m.drawstates()
m.fillcontinents(color='olive')
# draw parallels
delat=2.
circles=np.arange(17,27,delat)
m.drawparallels(circles,labels=[1,0,0,0])
# draw meridians
delon=5.
meridians=np.arange(-100,-60,delon)
m.drawmeridians(meridians,labels=[0,0,0,1])
plt.title('Equidistant Conic')
print('plotting Equidistant Conic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup lambert conformal map projection (North America).
m=Basemap(llcrnrlon=-145.5,llcrnrlat=1,urcrnrlon=-2.566,urcrnrlat=46.352,\
resolution='c',area_thresh=10000.,projection='lcc',\
lat_1=50.,lon_0=-107.)
# plot image over map.
cs=m.contourf(lons,lats,topodat,np.arange(-6500,5000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar(pad='10%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
m.drawstates()
#m.fillcontinents()
# draw parallels
delat=20.
circles=np.arange(0.,90.+delat,delat).tolist()+\
np.arange(-delat,-90.-delat,-delat).tolist()
m.drawparallels(circles,labels=[1,1,0,1])
# draw meridians
delon=30.
meridians=np.arange(10.,360.,delon)
m.drawmeridians(meridians,labels=[1,1,0,1])
plt.title('Lambert Conformal Conic')
print('plotting Lambert Conformal example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup albers equal area map projection (Europe).
m=Basemap(llcrnrlon=-10.,llcrnrlat=20,urcrnrlon=55.,urcrnrlat=75,\
resolution='l',projection='aea',\
lat_1=40.,lat_2=60,lon_0=35.)
# plot image over map.
cs=m.contourf(lons,lats,topodat,np.arange(-4000,3000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar(pad='10%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
# draw parallels
delat=20.
circles=np.arange(0.,90.+delat,delat).tolist()+\
np.arange(-delat,-90.-delat,-delat).tolist()
m.drawparallels(circles,labels=[1,1,1,1])
# draw meridians
delon=30.
meridians=np.arange(10.,360.,delon)
m.drawmeridians(meridians,labels=[1,1,1,1])
plt.title('Albers Equal Area Conic',y=1.075)
print('plotting Albers Equal Area example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup stereographic map projection (Southern Hemisphere).
#m = Basemap(llcrnrlon=120.,llcrnrlat=0.,urcrnrlon=-60.,urcrnrlat=0.,\
# resolution='c',area_thresh=10000.,projection='stere',\
# lat_0=-90.,lon_0=75.,lat_ts=-90.)
# this is equivalent, but simpler.
m=Basemap(lon_0=75.,boundinglat=-20,
resolution='c',area_thresh=10000.,projection='spstere')
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(pad='12%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
#m.fillcontinents()
# draw parallels
m.drawparallels(circles)
# draw meridians
m.drawmeridians(meridians,labels=[1,1,1,1])
plt.title('Square Polar Stereographic',y=1.075)
print('plotting Square Stereographic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
m=Basemap(lon_0=75.,boundinglat=-20,
resolution='c',area_thresh=10000.,projection='spstere',round=True)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(pad='12%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
#m.fillcontinents()
# draw parallels.
m.drawparallels(circles)
# draw meridians
m.drawmeridians(meridians,labels=[1,1,1,1])
plt.title('Round Polar Stereographic',y=1.075)
print('plotting Round Stereographic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup lambert azimuthal map projection (Northern Hemisphere).
m=Basemap(llcrnrlon=-150.,llcrnrlat=-18.,urcrnrlon=30.,urcrnrlat=--18.,\
resolution='c',area_thresh=10000.,projection='laea',\
lat_0=90.,lon_0=-105.)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(pad='12%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
m.drawstates()
#m.fillcontinents()
# draw parallels
m.drawparallels(circles)
# draw meridians
m.drawmeridians(meridians,labels=[1,1,1,1])
plt.title('Square Lambert Azimuthal Equal Area',y=1.075)
print('plotting Square Lambert Azimuthal example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
m=Basemap(projection='rotpole',lon_0=-120.,\
o_lon_p=180, o_lat_p=0,\
llcrnry=-41.75, urcrnry=37.75,\
llcrnrx=137, urcrnrx=222.5, resolution='l')
m.drawcoastlines()
ny,nx=lons.shape
m.contourf(lons[ny//2:,:],lats[ny//2:,:],topodat[ny//2:,:],50,cmap=cmap,extend='both',latlon=True)
m.drawmeridians(np.arange(-180,180,20),labels=[1,1,1,1])
m.drawparallels(np.arange(20,80,20))
m.colorbar()
plt.title('Rotated Pole',y=1.075)
print('plotting Rotated Pole example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
m=Basemap(lon_0=-105,boundinglat=20.,
resolution='c',area_thresh=10000.,projection='nplaea',round=True)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(pad='12%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
m.drawstates()
#m.fillcontinents()
# draw parallels.
m.drawparallels(circles)
# draw meridians
m.drawmeridians(meridians,labels=[1,1,1,1])
plt.title('Round Lambert Azimuthal Equal Area',y=1.075)
print('plotting Round Lambert Azimuthal example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup azimuthal equidistant map projection (Northern Hemisphere).
#m = Basemap(llcrnrlon=-150.,llcrnrlat=40.,urcrnrlon=30.,urcrnrlat=40.,\
# resolution='c',area_thresh=10000.,projection='aeqd',\
# lat_0=90.,lon_0=-105.)
# this is equivalent, but simpler.
m=Basemap(lon_0=-105,boundinglat=55.,
resolution='c',area_thresh=10000.,projection='npaeqd')
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
# plot image over map.
im=m.imshow(topodat,plt.cm.jet)
m.colorbar(pad='12%') # draw colorbar
m.drawcoastlines()
m.drawcountries()
m.drawstates()
#m.fillcontinents()
# draw parallels
m.drawparallels(circles)
# draw meridians
m.drawmeridians(meridians,labels=[1,1,1,1])
plt.title('Azimuthal Equidistant',y=1.075)
print('plotting Azimuthal Equidistant example ...')
print(m.proj4string)

# projections with elliptical boundaries (orthographic, sinusoidal,
# mollweide and robinson)

# create new figure
fig=plt.figure()
# setup of basemap ('ortho' = orthographic projection)
m=Basemap(projection='ortho',
resolution='c',area_thresh=10000.,lat_0=30,lon_0=-60)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar() # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians (labelling is
# not implemented for orthographic).
parallels=np.arange(-80.,90,20.)
m.drawparallels(parallels)
meridians=np.arange(0.,360.,20.)
m.drawmeridians(meridians)
# draw boundary around map region.
plt.title('Orthographic')
print('plotting Orthographic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('geos' = geostationary projection)
m=Basemap(projection='geos',
rsphere=(6378137.00,6356752.3142),\
resolution='c',area_thresh=10000.,lon_0=0,satellite_height=35785831)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar() # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians (labelling is
# not implemented for geostationary).
parallels=np.arange(-80.,90,20.)
m.drawparallels(parallels)
meridians=np.arange(0.,360.,20.)
m.drawmeridians(meridians)
# draw boundary around map region.
plt.title('Geostationary')
print('plotting Geostationary example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of sinusoidal ('sinu' = sinusioidal projection)
m=Basemap(projection='sinu',
resolution='c',area_thresh=10000.,lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,30.)
m.drawmeridians(meridians)
# draw boundary around map region.
plt.title('Sinusoidal')
print('plotting Sinusoidal example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('moll' = mollweide projection)
m=Basemap(projection='moll',
resolution='c',area_thresh=10000.,lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,30.)
m.drawmeridians(meridians)
# draw boundary around map region.
plt.title('Mollweide')
print('plotting Mollweide example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('hammer' = Hammer projection)
m=Basemap(projection='hammer',
resolution='c',area_thresh=10000.,lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,30.)
m.drawmeridians(meridians)
# draw boundary around map region.
plt.title('Hammer')
print('plotting Hammer example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('robin' = robinson projection)
m=Basemap(projection='robin',
resolution='c',area_thresh=10000.,lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom',pad='10%') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,60.)
m.drawmeridians(meridians,labels=[0,0,0,1])
# draw boundary around map region.
plt.title('Robinson')
print('plotting Robinson example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('kav7' = Kavrayskiy VII projection)
m=Basemap(projection='kav7',
resolution='c',area_thresh=10000.,lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom',pad='10%') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,60.)
m.drawmeridians(meridians,labels=[0,0,0,1])
# draw boundary around map region.
plt.title('Kavrayskiy VII')
print('plotting Kavrayskiy VII example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('eck4' = Eckert IV projection)
m=Basemap(projection='eck4',
resolution='c',area_thresh=10000.,lon_0=0)
cs=m.contourf(lons,lats,topodat,50,cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom',pad='10%') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,60.)
m.drawmeridians(meridians,labels=[0,0,0,1])
# draw boundary around map region.
plt.title('Eckert IV')
print('plotting Eckert IV example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# setup of basemap ('mbtfpq' = McBryde-Thomas Flat Polar Quartic projection)
m=Basemap(projection='mbtfpq',
resolution='c',area_thresh=10000.,lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,np.arange(-6500,5000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar(location='bottom') # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-60.,90,30.)
m.drawparallels(parallels,labels=[1,0,0,0])
meridians=np.arange(0.,360.,60.)
m.drawmeridians(meridians,labels=[0,0,0,1],fontsize=8)
# draw boundary around map region.
plt.title('McBryde-Thomas Flat Polar Quartic')
print('plotting McBryde-Thomas Flat Polar Quartic example ...')
print(m.proj4string)

# create new figure
fig=plt.figure()
# create Basemap instance for van der Grinten projection.
m=Basemap(projection='vandg',lon_0=0)
# plot image over map.
cs=m.contourf(lons,lats,topodat,np.arange(-6500,5000,50),cmap=cmap,extend='both',latlon=True)
m.colorbar() # draw colorbar
# draw coastlines and political boundaries.
m.drawcoastlines()
# draw parallels and meridians
parallels=np.arange(-80.,90,20.)
m.drawparallels(parallels)
meridians=np.arange(0.,360.,60.)
m.drawmeridians(meridians)
# draw boundary around map region.
# add a title.
plt.title('van der Grinten')
print('plotting van der Grinten example ...')
print(m.proj4string)

plt.show()

print('done')