The plotmap class provides easy wrappers to the Matplotlib basemap module, enabling you to plot maps more quickly.

Clone the repository to a location that you can add to your PYTHONPATH.

Dependencies:

• Georaster
• matplotlib basemap
• matplotlib

import plotmap

mymap = plotmap.Map(**kwargs)

The Map object must be created with georeferencing information. This can be provided in three ways:

1. With the ds_file argument : str, link to a raster dataset understood by GeoRaster. The extent of the plotting area and the lon_0 will be set according to the properties of the dataset.

2. With the georaster argument : a Georaster SingleBandRaster or MultiBandRaster instance.

3. By setting extent and lon_0 manually :

   extent = (lon_lower_left,lon_upper_right,lat_lower_left,lat_upper_right) lon_0 = float, longitude of origin

By default a new matplotlib Figure will be created and new Axes to contain the map. You may optionally control the size of the new figure by passing figsize=(x,y).

Alternatively, provide an existing Axes, in which case figsize is ignored, e.g.:

fig = plt.figure(figsize(6,6))
ax = plt.subplot(111)
mymap = plotmap.Map(fig=fig,ax=ax,**kwargs)

You can then get access to the following references:

• mymap.map : matplotlib basemap instance of the map
• mymap.fig : Figure handle
• mymap.ax : Axes handle
• mymap.extent : (xmin,xmax,ymin,ymax) of the map area

You can either use any of the several simple functions provided to add data to the map, e.g.:

myimage = georaster.SingleBandRaster('myimg.tif')
mymap.plot_data(myimage)

Or for more complicated cases you can use matplotlib directly to add raster data:

myimage = georaster.SingleBandRaster('myimg.tif')
plt.gca()
# GeoRaster loads band data into r attribute
# The basemap instance exposed by mymap.map is a pyproj conversion 
# function between the map projection system and WGS84.
plt.imshow(myimage.r,extent=myimage.get_extent_projected(mymap.map))

Shapefiles can also be plotted (no simple functions to do this yet, to do) by first loading them in using Basemap's readshapefile() function:

shp_info = mymap.map.readshapefile('file','name',drawbounds=False)
for shape,shapedict in zip(mymap.map.name,mymap.map.name_info):
    xx,yy = zip(*shape)
    mymap.map.plot(xx,yy)

Add point data:

x,y = mymap.map(lon,lat)
plt.plot(x,y,'^k')

Create a scale bar (various **kwargs available):

scale_obj = mymap.plot_scale(length)

Add a geographic grid:

mymap.geo_ticks(x_spacing,y_spacing)

Add a colorbar (various **kwargs available):

cbar = mymap.plot_colorbar()