Script for taking polyline shapefile to a Polygon shapefile using shapely 1.4.4 - https://pypi.python.org/pypi/Shapely ( Windows binary - http://www.lfd.uci.edu/~gohlke/pythonlibs/#shapely ) and fiona 1.4.8 - https://pypi.python.org/pypi/Fiona. Useful for Ordnance Survey coastline data, the polylines to polygons function in QGIS 2.6 used an olde…

polyline_to_polygon.py

from shapely.geometry import mapping
from shapely.ops import polygonize
import fiona

def polyline_to_polygon(input_file, output_file):
    polylines = fiona.open(input_file)
    geom = [x['geometry'] for x in polylines]
    coords = [x['coordinates']for x in geom[:-1]]
    schema = {'geometry': 'Polygon','properties': {'id': 'int'}}
    with fiona.open(output_file, 'w', 'ESRI Shapefile', schema) as c:
        for poly_id,polygon in enumerate(polygonize(coords)):
            c.write({
                'geometry': mapping(polygon),
                'properties': {'id': poly_id},
            })