geojsoncontour 0.1.2

A Python 3 module to convert matplotlib contour plots to geojson.

Designed to show geographical contour plots, created with matplotlib/pyplot, as vector layer on interactive slippy maps like OpenLayers and Leaflet.

Demo project that uses geojsoncontour: climatemaps.romgens.com

Currently only supports contour lines.

Installation

The recommended way to install is via pip,

$ pip install geojsoncontour

Usage

Contour plot to geojson

import numpy
import matplotlib.pyplot as plt
import geojsoncontour

# Create contour data lon_range, lat_range, Z
<your code here>

# Create a contour plot plot from grid (lat, lon) data
figure = plt.figure()
ax = figure.add_subplot(111)
contour = ax.contour(lon_range, lat_range, Z, levels=levels, cmap=plt.cm.jet)

# Convert matplotlib contour to geojson
geojsoncontour.contour_to_geojson(
    contour=contour,
    geojson_filepath='out.geojson',
    contour_levels=levels,
    ndigits=3,
    unit='m'
)

See example1.py for a basic but complete example.

Show the geojson on a map

An easy way to show the generated geojson on a map is the online geojson renderer geojson.io.

Style properties

Stroke color and width are set as geojson properties following https://github.com/mapbox/simplestyle-spec.

Create geojson tiles

Try geojson-vt or tippecanoe if performance is an issue and you need to tile your geojson contours.

Tests

Run all tests,

python -m unittest discover