Fix DeprecationWarning: using a non-integer number instead of an integer will result in an error in the future

Author: cgohlke

examples/streamplot_demo.py

@@ -15,7 +15,7 @@
 vdat=ncfile.variables['sfc_v'][0,:,:]
 lons1=ncfile.variables['longitude'][:]
 lats1=ncfile.variables['latitude'][:]
-lat0=lats1[len(lats1)/2]; lon0=lons1[len(lons1)/2]
+lat0=lats1[len(lats1)//2]; lon0=lons1[len(lons1)//2]
 lons, lats=np.meshgrid(lons1,lats1)
 ncfile.close()