Skip to main content

Geometric objects, predicates, and operations

Project description

Manipulation and analysis of geometric objects in the Cartesian plane.

http://farm3.staticflickr.com/2738/4511827859_b5822043b7_o_d.png

Shapely is a BSD-licensed Python package for manipulation and analysis of planar geometric objects. It is based on the widely deployed GEOS (the engine of PostGIS) and JTS (from which GEOS is ported) libraries. Shapely is not concerned with data formats or coordinate systems, but can be readily integrated with packages that are. For more details, see:

Requirements

Shapely 1.3 requires

  • Python >=2.6 (including Python 3.x)

  • libgeos_c >=3.1 (3.0 and below have not been tested, YMMV)

Installation

Windows users should use the executable installer, which contains the required GEOS DLL. Other users should acquire libgeos_c by any means, make sure that it is on the system library path, and install from the Python package index:

$ pip install Shapely

or from a source distribution with the setup script:

$ python setup.py install

Usage

Here is the canonical example of building an approximately circular patch by buffering a point:

>>> from shapely.geometry import Point
>>> patch = Point(0.0, 0.0).buffer(10.0)
>>> patch
<shapely.geometry.polygon.Polygon object at 0x...>
>>> patch.area
313.65484905459385

See the manual for comprehensive usage snippets and the dissolve.py and intersect.py example apps.

Integration

Shapely does not read or write data files, but it can serialize and deserialize using several well known formats and protocols. The shapely.wkb and shapely.wkt modules provide dumpers and loaders inspired by Python’s pickle module.:

>>> from shapely.wkt import dumps, loads
>>> dumps(loads('POINT (0 0)'))
'POINT (0.0000000000000000 0.0000000000000000)'

All linear objects, such as the rings of a polygon (like patch above), provide the Numpy array interface.:

>>> from numpy import asarray
>>> ag = asarray(patch.exterior)
>>> ag
array([[  1.00000000e+01,   0.00000000e+00],
       [  9.95184727e+00,  -9.80171403e-01],
       [  9.80785280e+00,  -1.95090322e+00],
       ...
       [  1.00000000e+01,   0.00000000e+00]])

That yields a Numpy array of [x, y] arrays. This is not always exactly what one wants for plotting shapes with Matplotlib (for example), so Shapely 1.2 adds a xy property for obtaining separate arrays of coordinate x and y values.:

>>> x, y = patch.exterior.xy
>>> ax = asarray(x)
>>> ax
array([  1.00000000e+01,   9.95184727e+00,   9.80785280e+00,  ...])

Numpy arrays can also be adapted to Shapely linestrings:

>>> from shapely.geometry import asLineString
>>> asLineString(ag).length
62.806623139095073
>>> asLineString(ag).wkt
'LINESTRING (10.0000000000000000 0.0000000000000000, ...)'

Shapely can also integrate with other Python GIS packages using data modeled after GeoJSON.

>>> import json
>>> from shapely.geometry import mapping, shape
>>> s = shape(json.loads('{"type": "Point", "coordinates": [0.0, 0.0]}'))
>>> s
<shapely.geometry.point.Point object at 0x...>
>>> print(json.dumps(mapping(s)))
{"type": "Point", "coordinates": [0.0, 0.0]}

Development and Testing

Dependencies for developing Shapely are listed in requirements-dev.txt. Cython and Numpy are not required for production installations, only for development. Use of a virtual environment is strongly recommended.:

$ virtualenv .
$ source bin/activate
(env)$ pip install -r requirements-dev.txt
(env)$ python setup.py develop

Shapely uses a Zope-stye suite of unittests and doctests, exercised via setup.py.:

(env)$ python setup.py test

Nosetests won’t run the tests properly; Zope doctest suites are not currently supported well by nose.

Support

Please discuss Shapely with us at http://lists.gispython.org/mailman/listinfo/community.

Bugs may be reported at https://github.com/Toblerity/Shapely.

Credits

Shapely is written by:

  • Sean Gillies

  • Aron Bierbaum

  • Kai Lautaportti

  • Oliver Tonnhofer

Patches contributed by:

See also: https://github.com/Toblerity/Shapely/graphs/contributors.

Additional help from:

  • Justin Bronn (GeoDjango) for ctypes inspiration

  • Martin Davis (JTS)

  • Jaakko Salli for the Windows distributions

  • Sandro Santilli, Mateusz Loskot, Paul Ramsey, et al (GEOS Project)

Major portions of this work were supported by a grant (for Pleiades) from the U.S. National Endowment for the Humanities (http://www.neh.gov).

Changes

1.3.2 (2014-05-13)

  • Let LineString() take a sequence of Points (#130).

1.3.1 (2014-04-22)

  • More reliable proxy cleanup on exit (#106).

  • More robust DLL loading on all platforms (#114).

1.3.0 (2013-12-31)

  • Include support for Python 3.2 and 3.3 (#56), minimum version is now 2.6.

  • Switch to GEOS WKT/WKB Reader/Writer API, with defaults changed to enable 3D output dimensions, and to ‘trim’ WKT output for GEOS >=3.3.0.

  • Use GEOS version instead of GEOS C API version to determine library capabilities (#65).

1.2.19 (2013-12-30)

  • Add buffering style options (#55).

1.2.18 (2013-07-23)

  • Add shapely.ops.transform.

  • Permit empty sequences in collection constructors (#49, #50).

  • Individual polygons in MultiPolygon.__geo_interface__ are changed to tuples to match Polygon.__geo_interface__ (#51).

  • Add shapely.ops.polygonize_full (#57).

1.2.17 (2013-01-27)

  • Avoid circular import between wkt/wkb and geometry.base by moving calls to GEOS serializers to the latter module.

  • Set _ndim when unpickling (issue #6).

  • Don’t install DLLs to Python’s DLL directory (#37).

  • Add affinity module of affine transformation (#31).

  • Fix NameError that blocked installation with PyPy (#40, #41).

1.2.16 (2012-09-18)

  • Add ops.unary_union function.

  • Alias ops.cascaded_union to ops.unary_union when GEOS CAPI >= (1,7,0).

  • Add geos_version_string attribute to shapely.geos.

  • Ensure parent is set when child geometry is accessed.

  • Generate _speedups.c using Cython when building from repo when missing, stale, or the build target is “sdist”.

  • The is_simple predicate of invalid, self-intersecting linear rings now returns False.

  • Remove VERSION.txt from repo, it’s now written by the distutils setup script with value of shapely.__version__.

1.2.15 (2012-06-27)

  • Eliminate numerical sensitivity in a method chaining test (Debian bug #663210).

  • Account for cascaded union of random buffered test points being a polygon or multipolygon (Debian bug #666655).

  • Use Cython to build speedups if it is installed.

  • Avoid stumbling over SVN revision numbers in GEOS C API version strings.

1.2.14 (2012-01-23)

  • A geometry’s coords property is now sliceable, yielding a list of coordinate values.

  • Homogeneous collections are now sliceable, yielding a new collection of the same type.

1.2.13 (2011-09-16)

  • Fixed errors in speedups on 32bit systems when GEOS references memory above 2GB.

  • Add shapely.__version__ attribute.

  • Update the manual.

1.2.12 (2011-08-15)

  • Build Windows distributions with VC7 or VC9 as appropriate.

  • More verbose report on failure to speed up.

  • Fix for prepared geometries broken in 1.2.11.

  • DO NOT INSTALL 1.2.11

1.2.11 (2011-08-04)

  • Ignore AttributeError during exit.

  • PyPy 1.5 support.

  • Prevent operation on prepared geometry crasher (#12).

  • Optional Cython speedups for Windows.

  • Linux 3 platform support.

1.2.10 (2011-05-09)

  • Add optional Cython speedups.

  • Add is_cww predicate to LinearRing.

  • Add function that forces orientation of Polygons.

  • Disable build of speedups on Windows pending packaging work.

1.2.9 (2011-03-31)

  • Remove extra glob import.

  • Move examples to shapely.examples.

  • Add box() constructor for rectangular polygons.

  • Fix extraneous imports.

1.2.8 (2011-12-03)

  • New parallel_offset method (#6).

  • Support for Python 2.4.

1.2.7 (2010-11-05)

  • Support for Windows eggs.

1.2.6 (2010-10-21)

  • The geoms property of an empty collection yields [] instead of a ValueError (#3).

  • The coords and geometry type sproperties have the same behavior as above.

  • Ensure that z values carry through into products of operations (#4).

1.2.5 (2010-09-19)

  • Stop distributing docs/_build.

  • Include library fallbacks in test_dlls.py for linux platform.

1.2.4 (2010-09-09)

  • Raise AttributeError when there’s no backend support for a method.

  • Raise OSError if libgeos_c.so (or variants) can’t be found and loaded.

  • Add geos_c DLL loading support for linux platforms where find_library doesn’t work.

1.2.3 (2010-08-17)

  • Add mapping function.

  • Fix problem with GEOSisValidReason symbol for GEOS < 3.1.

1.2.2 (2010-07-23)

  • Add representative_point method.

1.2.1 (2010-06-23)

  • Fixed bounds of singular polygons.

  • Added shapely.validation.explain_validity function (#226).

1.2 (2010-05-27)

  • Final release.

1.2rc2 (2010-05-26)

  • Add examples and tests to MANIFEST.in.

  • Release candidate 2.

1.2rc1 (2010-05-25)

  • Release candidate.

1.2b7 (2010-04-22)

  • Memory leak associated with new empty geometry state fixed.

1.2b6 (2010-04-13)

  • Broken GeometryCollection fixed.

1.2b5 (2010-04-09)

  • Objects can be constructed from others of the same type, thereby making copies. Collections can be constructed from sequences of objects, also making copies.

  • Collections are now iterators over their component objects.

  • New code for manual figures, using the descartes package.

1.2b4 (2010-03-19)

  • Adds support for the “sunos5” platform.

1.2b3 (2010-02-28)

  • Only provide simplification implementations for GEOS C API >= 1.5.

1.2b2 (2010-02-19)

  • Fix cascaded_union bug introduced in 1.2b1 (#212).

1.2b1 (2010-02-18)

  • Update the README. Remove cruft from setup.py. Add some version 1.2 metadata regarding required Python version (>=2.5,<3) and external dependency (libgeos_c >= 3.1).

1.2a6 (2010-02-09)

  • Add accessor for separate arrays of X and Y values (#210).

TODO: fill gap here

1.2a1 (2010-01-20)

  • Proper prototyping of WKB writer, and avoidance of errors on 64-bit systems (#191).

  • Prototype libgeos_c functions in a way that lets py2exe apps import shapely (#189).

1.2 Branched (2009-09-19)

1.0.12 (2009-04-09)

  • Fix for references held by topology and predicate descriptors.

1.0.11 (2008-11-20)

  • Work around bug in GEOS 2.2.3, GEOSCoordSeq_getOrdinate not exported properly (#178).

1.0.10 (2008-11-17)

  • Fixed compatibility with GEOS 2.2.3 that was broken in 1.0.8 release (#176).

1.0.9 (2008-11-16)

  • Find and load MacPorts libgeos.

1.0.8 (2008-11-01)

  • Fill out GEOS function result and argument types to prevent faults on a 64-bit arch.

1.0.7 (2008-08-22)

  • Polygon rings now have the same dimensions as parent (#168).

  • Eliminated reference cycles in polygons (#169).

1.0.6 (2008-07-10)

  • Fixed adaptation of multi polygon data.

  • Raise exceptions earlier from binary predicates.

  • Beginning distributing new windows DLLs (#166).

1.0.5 (2008-05-20)

  • Added access to GEOS polygonizer function.

  • Raise exception when insufficient coordinate tuples are passed to LinearRing constructor (#164).

1.0.4 (2008-05-01)

  • Disentangle Python and topological equality (#163).

  • Add shape(), a factory that copies coordinates from a geo interface provider. To be used instead of asShape() unless you really need to store coordinates outside shapely for efficient use in other code.

  • Cache GEOS geometries in adapters (#163).

1.0.3 (2008-04-09)

  • Do not release GIL when calling GEOS functions (#158).

  • Prevent faults when chaining multiple GEOS operators (#159).

1.0.2 (2008-02-26)

  • Fix loss of dimensionality in polygon rings (#155).

1.0.1 (2008-02-08)

  • Allow chaining expressions involving coordinate sequences and geometry parts (#151).

  • Protect against abnormal use of coordinate accessors (#152).

  • Coordinate sequences now implement the numpy array protocol (#153).

1.0 (2008-01-18)

  • Final release.

1.0 RC2 (2008-01-16)

  • Added temporary solution for #149.

1.0 RC1 (2008-01-14)

  • First release candidate

Project details


Release history Release notifications | RSS feed

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

Shapely-1.3.2.tar.gz (120.2 kB view details)

Uploaded Source

Built Distributions

Shapely-1.3.2.win-amd64-py3.4.exe (2.0 MB view details)

Uploaded Source

Shapely-1.3.2.win-amd64-py2.7.exe (2.3 MB view details)

Uploaded Source

Shapely-1.3.2.win32-py3.4.exe (1.7 MB view details)

Uploaded Source

Shapely-1.3.2.win32-py2.7.exe (1.7 MB view details)

Uploaded Source

File details

Details for the file Shapely-1.3.2.tar.gz.

File metadata

  • Download URL: Shapely-1.3.2.tar.gz
  • Upload date:
  • Size: 120.2 kB
  • Tags: Source
  • Uploaded using Trusted Publishing? No

File hashes

Hashes for Shapely-1.3.2.tar.gz
Algorithm Hash digest
SHA256 9f0de51c71373fcee4962f79f4813d67ea1e711f4394d7636c929a4019c5c2ff
MD5 51708994dd83360cfe66277b4764b23c
BLAKE2b-256 496e80054002de41698b525ce520af0ee0a259df23006d63c7af661939cf526f

See more details on using hashes here.

File details

Details for the file Shapely-1.3.2.win-amd64-py3.4.exe.

File metadata

File hashes

Hashes for Shapely-1.3.2.win-amd64-py3.4.exe
Algorithm Hash digest
SHA256 e56cfc461b3b8ea69e3be73dd631e103b6299a267fae933092cb493a61ad177d
MD5 47e28316d943642e746f95483957891d
BLAKE2b-256 1ee60d9df14143e0552bbc1fc4f516800e0c970aea5ba60460e8e74bbbc73cd5

See more details on using hashes here.

File details

Details for the file Shapely-1.3.2.win-amd64-py2.7.exe.

File metadata

File hashes

Hashes for Shapely-1.3.2.win-amd64-py2.7.exe
Algorithm Hash digest
SHA256 8ae7222b306443bd0d6c64e7705f5e8a00888671c9b156b4283e7f7319b0e157
MD5 b21fd4ba738a1366485b35193d223fc1
BLAKE2b-256 2773c45395dec8016c898792f81d5e9306719e43760d51fab43017a796ecd476

See more details on using hashes here.

File details

Details for the file Shapely-1.3.2.win32-py3.4.exe.

File metadata

File hashes

Hashes for Shapely-1.3.2.win32-py3.4.exe
Algorithm Hash digest
SHA256 79d693eecaa72777d8e6dde3998023d1bd4431de5869e4ead0113951ec102a60
MD5 c38708966f70c5f67d467ac923007129
BLAKE2b-256 68d42cdbdffe3c5718e8d510b8b19ac5f5f9192fe7b9d89457f47ea1a28547fb

See more details on using hashes here.

File details

Details for the file Shapely-1.3.2.win32-py2.7.exe.

File metadata

File hashes

Hashes for Shapely-1.3.2.win32-py2.7.exe
Algorithm Hash digest
SHA256 f55c043e9b018dbf451fe96fc1a7e25cd274b380b59892eee99b440f738f0e84
MD5 f26a250a0604463a386cb38b818f7e8a
BLAKE2b-256 d2abd053767df4001941b43e6f78265d292d97ce52123e1ef54091d567a42bf4

See more details on using hashes here.

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page