smoomapy 0.1.1

Make smoothed maps from a geo layer

Make smoothed maps in your python environnement

More or less a python port of Stewart method from R SpatialPositon package (https://github.com/Groupe-ElementR/SpatialPosition/) Allow to set a desired number of class and choose discretization method or directly set some custom breaks values. Input/output can be a path to a geographic layer (GeoJSON, shp, etc.) or a GeoDataFrame.

Requires:

• Numpy

• GeoPandas

• SciPy

• Matplotlib

Documentation on the method :

Please refer to https://github.com/Groupe-ElementR/SpatialPosition/ documentation.

Usage example:

One-shot functionnality

>>> result = quick_stewart('nuts3_data.geojson',
                           "pop1999",
                           span=65000,
                           beta=3,
                           resolution=48000,
                           mask='nuts3_data.geojson',
                           nb_class=10,
                           user_defined_breaks=None,
                           output="geojson")

Object-oriented API, allowing to easily redraw contours with new breaks values or new interpolation functionnality

>>> StePot = SmoothStewart('nuts3_data.geojson', "pop1999",
                       span=65000, beta=3,
                       resolution=60000,
                       mask='nuts3_data.geojson')
>>> res = StePot.render(nb_class=8, func_grid="matplotlib",
                        disc_func="jenks", output="GeoDataFrame")
>>> res.plot(cmap="YlOrRd", linewidth=0.1)

The long part of the computation is done during the initialization of SmoothStewart instance (i.e. actually computing potentials). Some convenience methods allows to tweak and re-export the few last steps :

*Allow to quickly redraw polygons with a new classification method (or with new interpolation functionnality)* Availables classification methods are: “equal_interval”, “prog_geom”, “jenks”, “percentiles” and “head-tail-breaks”

>>> StePot.change_interp_grid_shape((164, 112))

>>> res = StePot.render(nb_class=6, func_grid="scipy",
                        disc_func="percentiles", output="GeoDataFrame")

*Allow to set custom break values (highly recommended after a first rendering or having take a look at the distibution):*

>>> my_breaks = [0, 1697631, 3395263, 5092894, 6790526,
                 8488157, 10185789, 11883420, 13581052]

>>> res = StePot.render(nb_class=6, user_defined_breaks=my_breaks,
                        output="GeoDataFrame")

*Some other smoothing methods can be used (experimental!) :*

>>> res = StePot.render(nb_class=12, func_grid="rbf", output="GeoDataFrame")

Installation:

From PyPI :

$ pip install smoomapy

From github :

$ git clone http://github.com/mthh/smoomapy.git
$ cd smoomapy/
$ python setup.py install