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Introduction

I've been working on this shapefile python class since 2010. It allows for the easy reading, creation and updating of shapefiles using OGR.

OGR is a prerequisite: from osgeo import ogr OR import ogr I extensively used the documentation from http://www.gis.usu.edu/~chrisg/python/2009/docs.html, especially http://www.gis.usu.edu/~chrisg/python/2009/docs/ogr.pdf

Installation

Simply save shapefile.py in your work folder and call: from shapefile import shapefile

Read shapefile

shpfile = "filename.shp"
shp = shapefile("read", shpfile)
for feat in shp.features: # shp.features is a simple python list with all the features loaded.
    attr_dict = shp.attr_dict(feat)
    # do something
shp.finish()

attr_dict example

{"FID": 1 , "NAME": "John"}

Write shapefile

shpfile = "filename.shp"
inshp = shapefile("read", shpfile)
outshp = shapefile("write", shpfile[:-4] + "_new.shp", inshp.type, inshp.fieldslist, inshp.projection)
for feat in inshp.features:
    attr_dict = inshp.attr_dict(feat)
    # do something with feat or attr_dict
    outshp.createfeat(feat, attr_dict)
inshp.finish()
outshp.finish()

Projections

Projections are internally saved as ESRI format strings: shp.projection = ["ESRI", 'projection string'] But can be provided as: projection = ["PROJ4", 'projection string'] projection = ["EPSG", number]

Update shapefile

With new field:

shpfile = "filename.shp"
shp = shapefile("update", shpfile)
if not shp.fieldexist('NAME'):
    shp.createfield(['NAME', 2, 10, 8])

for feat in shp.features:
    shp.updatefield(feat, 'NAME', 1)
shp.finish()

By deleting feature:

shpfile = "filename.shp"
shp = shapefile("update", shpfile)

for feat in shp.features:
    if <some logic>:
        shp.deletefeat(feat)
shp.finish()

Select

Loop through all features with a certain field name value:

shp = shapefile("read", shpfile)
values = shp.fieldvaluelist('NAME', doubles=0) # default doubles=1 
for value in values:
    layer_select = shp.selectfeats('NAME', value)
    for feat in layer_select:
        # do something
shp.finish()