app/django/contrib/gis/utils/wkt.py
author Lennard de Rijk <ljvderijk@gmail.com>
Mon, 16 Feb 2009 20:38:35 +0000
changeset 1364 b2709805fafe
parent 323 ff1a9aa48cfd
permissions -rw-r--r--
Update org bulk accept script. The script now: 1) leaves correctly control to the browser to update the GUI of the progress bar during ajax communication. 2) Displays an error if something went wrong (I've tried in my box stopping the server while doing the requests), and show a retry button to fetch again the list of the applications that are still not accepted and iterate over them again (seems to recover correctly restarting the server after the error in my box) 3) doesn't display any text at the beginning, and the button has the correct CSS class assigned 4) Check if there are applications to accept, if not displays a message stating that there are no orgs to accept. Patch by: Mario Ferraro Reviewed by: Lennard de Rijk

"""
 Utilities for manipulating Geometry WKT.
"""

def precision_wkt(geom, prec):
    """
    Returns WKT text of the geometry according to the given precision (an 
    integer or a string).  If the precision is an integer, then the decimal
    places of coordinates WKT will be truncated to that number:

     >>> pnt = Point(5, 23)
     >>> pnt.wkt
     'POINT (5.0000000000000000 23.0000000000000000)'
     >>> precision(geom, 1)
     'POINT (5.0 23.0)'

    If the precision is a string, it must be valid Python format string 
    (e.g., '%20.7f') -- thus, you should know what you're doing.
    """
    if isinstance(prec, int):
        num_fmt = '%%.%df' % prec
    elif isinstance(prec, basestring):
        num_fmt = prec
    else:
        raise TypeError

    # TODO: Support 3D geometries.
    coord_fmt = ' '.join([num_fmt, num_fmt])

    def formatted_coords(coords):
        return ','.join([coord_fmt % c[:2] for c in coords])

    def formatted_poly(poly):
        return ','.join(['(%s)' % formatted_coords(r) for r in poly])

    def formatted_geom(g):
        gtype = str(g.geom_type).upper()
        yield '%s(' % gtype
        if gtype == 'POINT':
            yield formatted_coords((g.coords,))
        elif gtype in ('LINESTRING', 'LINEARRING'):
            yield formatted_coords(g.coords)
        elif gtype in ('POLYGON', 'MULTILINESTRING'):
            yield formatted_poly(g)
        elif gtype == 'MULTIPOINT':
            yield formatted_coords(g.coords)
        elif gtype == 'MULTIPOLYGON':
            yield ','.join(['(%s)' % formatted_poly(p) for p in g])
        elif gtype == 'GEOMETRYCOLLECTION':
            yield ','.join([''.join([wkt for wkt in formatted_geom(child)]) for child in g])
        else:
            raise TypeError
        yield ')'

    return ''.join([wkt for wkt in formatted_geom(geom)])