In [4]: a=fromfile("pr.dec",float32).byteswap().reshape(220,250)

In [5]: a
Out[5]: 
array([[-999., -999., -999., ..., -999., -999., -999.],
       [-999., -999., -999., ..., -999., -999., -999.],
       [-999., -999., -999., ..., -999., -999., -999.],
       ..., 
       [-999., -999., -999., ..., -999., -999., -999.],
       [-999., -999., -999., ..., -999., -999., -999.],
       [-999., -999., -999., ..., -999., -999., -999.]], dtype=float32)

In [6]: imshow(a)
Out[6]: <matplotlib.image.AxesImage instance at 0x200000000519fcb0>

In [7]: from matplotlib.toolkits.basemap import Basemap

In [8]: M=Basemap(urcrnrlat=50,urcrnrlon=150,llcrnrlat=25,llcrnrlon=125, resolution='l') 

In [9]: M1=Basemap(urcrnrlat=50,urcrnrlon=150,llcrnrlat=25,llcrnrlon=125, resolution='c')

In [10]: M.drawcoastlines()

In [11]: show()

In [12]: M.imshow(a);M.drawco
M.drawcoastlines  M.drawcountries   

In [12]: M.imshow(a);M.drawcoastlines()
Out[12]: <matplotlib.image.AxesImage instance at 0x2000000006532c68>

In [13]: M.imshow(flipud(a));M.drawcoastlines()
Out[13]: <matplotlib.image.AxesImage instance at 0x20000000066617e8>

In [14]: M.imshow(flipud(a));M.drawcoastlines();show()
Out[14]: <matplotlib.image.AxesImage instance at 0x2000000006671c68>

In [15]: M1.imshow(flipud(a));M.drawcoastlines();show()
\Out[15]: <matplotlib.image.AxesImage instance at 0x20000000065e6170>

In [16]: M1.imshow(flipud(a));M.drawcoastlines();show()
Out[16]: <matplotlib.image.AxesImage instance at 0x20000000065fc4d0>

In [17]: M1.imshow(flipud(a));M1.drawcoastlines();show()
Out[17]: <matplotlib.image.AxesImage instance at 0x20000000067cb560>