Shapely is a BSD-licensed Python package for manipulation and analysis of planar geometric objects.

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2answers
44 views

Shapely: Round Polygon Corners?

I use the python module "shapely" to make Polygons (like below). Can I convert the sharp edges of a polygon easily to round edges? Such that when I have unified some polygons I could issue a command ...
1
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2answers
222 views

problems with py2exe, shapely and fiona

I have a short python script, called test: import fiona with fiona.open("C:\\Essai_compil", 'r') as l_Obs_shp: for shp in l_Obs_shp: print shp['geometry'] I want to compile with ...
0
votes
1answer
126 views

Calculating intersection between points and polygon in shapefile

I want accomplish the following using command line python tools only (shapely + fiona) I was wondering if there was a straightforward way for me to do the following: Read in a shapefile (all ...
7
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1answer
327 views

How to split two interscting polygons by the average linestring of the shared area (QGIS / python shapely)

I have two polygons, POLYGON((-5 -5,-5 5,5 5,5 -5,-5 -5)) POLYGON((1 1, 1 7, 7 7, 7 1, 1 1)) and wish to split them evenly. The result should be a split along the red marked line. I'm using ...
1
vote
1answer
45 views

Equivalent function to shapely's envelope in ogr?

I wrote a very simple python function that gives me the envelope/bounding box/...based on two coordinate pairs (ower left and upper right corner): # ... def get_bounding_box(self, ll_corner, ...
0
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1answer
186 views

Shapely LineString and Polygon intersect?

here is my python code, it does not intersect and when I plot this in google map , I see the intersection. shapely.geometry is in Cartesian plane, how you are solving this? l = "40.65:-114.07 ...
3
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2answers
465 views

Creating Shapely MultiPolygons from shape file MultiPolygons

I'm reading a shapefile using Fiona: with fiona.open('data/boroughs/boroughs_n.shp') as source: mpolys = [p for p in source] candidate = polys[0]['geometry'] this gives me a dict containing a ...
5
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3answers
2k views

How to write Shapely geometries to shapefiles?

Can someone demonstrate a simple way to write geometry data-structures from shapely into shapefiles? I am particularly interested in polygons with holes and linestrings. It would also be beneficial to ...
0
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0answers
49 views

Fastest way to add shapely geometries to a PostGis database using geoalchemy2

I am looking for the absolute fastest approach to adding +10,000 shapely geometry objects to a PostGIS database using geoalchemy2. I'm having no speed issues when uploading to a localhost postgres ...
3
votes
2answers
136 views

how would one get the end points of a polyline?

I am attempting to write a script to get the end points of a series polylines, and then use those end points to create a polygon. I'm not sure which tools to begin to use on this project. I would ...
3
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2answers
761 views

How to install shapely for python 2.6 (Mac) NOT 2.7?

I'm trying to use Polygonizer plugin inside QGIS, but it needs Shapely to work. I've installed Shapely (pip install Shapely) but that's for python 2.7. QGIS works with python 2.6 (on Snow Leopard) and ...
0
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0answers
9 views

How to create a shapely multipolygon from GADM shapelife? [duplicate]

I am using GADM (http://gadm.org/country) to get shapefiles from administrative areas anywhere in the world (trying with the US at the moment). To read the shapefile I am using Fiona in python. This ...
1
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2answers
62 views

Get the vertices on a LineString either side of a Point

I have a shapely LineString and defined a shapely Point which lies along the LineString. How can I find the vertices of the LineString which lie either side of the point? (split the line in two). ...
1
vote
1answer
45 views

create a pie shaped object in shapely and export to gis polygon object

I would like to create a pie chart-shaped polygon with concentric layers like so: I can create this simple object with: from math import sin, cos, radians from shapely.geometry import ...
5
votes
1answer
135 views

Shapely unable to tell if polygon contains point

For an application I want to determine under which constituency a given coordinate falls. After looking at the various options, I decided upon shapely and fiona as the easiest way to implement this. ...
1
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2answers
86 views

Shapely MultiPolygon Construction - Will not accept the entire set of Polygons

I am new to Shapely, so I am using a work request to learn a bit more about it. I need to execute a number of unions to build larger geometries from assessment neighborhoods in DC. I am curious ...
3
votes
1answer
78 views

Serialize python list containing geometry

In simple case if list doesn't contains geometry all works fine: result = [dict(f.fields, id=f.id, label=f.label) for f in features] json.dumps(result) But if result list contains geometry ...
0
votes
1answer
63 views

Shapely Python NameError when using cascaded_union

I am fairly new to Python and therefore my error-solving skills are not much yet developed. I am using Python within a geoprocessing script which is supposed to use ogr (reading/writing shp) and ...
6
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1answer
300 views

Find Nearest Line Segments to Point

Background From a known Point, I require to establish the nearest surrounding "visible perimeter" against a table of MultiLineStrings, as shown on the diagram. I've searched this site with a number ...
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2answers
182 views

What is the unit the shapely length attribute?

I'm doing a very simple calculation of the length of a polyline using shapely: from shapely.geometry import LineString ... xy_list = [map(float,e) for e in xy_intm] line = LineString(xy_list) s = ...
0
votes
1answer
159 views

Finding differences between two shapefiles in Python

I'm trying to find out whether there were any border changes between two yearly shapefiles. I've heard a lot of praise for Python's open source GIS tools like Shapely/Fiona, and thought I would try ...
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2answers
510 views

Determine if point is within an irregular polygon using Python

I would like to create a mask of a grid where points are evaluated as either 1's or 0's depending on if they lay outside of an irregular (i.e. not rectangular) polygon. I have a set of high-latitude ...
4
votes
1answer
563 views

Wrap GEOS functionality into python

I've been looking on how to get GEOSExtractLine available in python. I looked into Shapely source to if it was available for it, but it's not. I'm trying to wrap this funcionality into Django, much ...
2
votes
1answer
151 views

Fiona - Preffered method for defining a schema

I'm fairly new to the world of python and GIS - so this is definitely a beginner question. I am following Tom Macwrights small guide to Shapely and Fiona, and I noticed that even when opening the ...
2
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2answers
175 views

Does shapely within function identify inner holes?

I have a series of shapefiles that include both polygons and multipolygons. I am using ogr to extract them in wkb, and them I am using shapely to check if a point fall inside a polygon (or a ...
0
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0answers
133 views

Computing percentage of similarity between two line strings using python shapely

I'm quite new to shapely, been tinkering with it and I have a necessity to compare two line strings and see what percentage of them overlap. The geographic coordinates come from two different systems. ...
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0answers
120 views

How to shift vertices of shapes in shapefile using FOSS python library?

I need to shift each vertice of shape in a shapefile (of any type:point, line, polygon, multiline etc.) with Python. I need to loop in all shapes, get the vertices, get it's coordinates and for each ...
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2answers
222 views

Convert 3D WKT to 2D Shapely Geometry

I have the WKT of many linestrings which contains three dimensions, however my script only requires a two dimensional linestring and I therefore want to discard the third dimension. My current code, ...
4
votes
1answer
162 views

How to generate overlapping polygons from lines output from Table To Ellipse tool?

I have a feature class of line-based ellipses generated by the Table to Ellipse tool that looks like this: What I want is polygons of the individual ellipses, however tools like Feature to Polygon ...
4
votes
4answers
312 views

How to computational efficiently check if there are any overlapping polygons in a group of polygons?

I need to do some processing with groups of polygons. If any of the polygons in the group overlaps other polygon the result is unpredictable and don't throw any error. So, I need to detect if there is ...
2
votes
1answer
282 views

How to install shapely on Ubuntu 12.10

I have tried to install shapely on Ubuntu 12.10. Therefore I installed libgeos-c1, pip and shapely with $ pip install Shapely. The shapely files are now in /home/user/build/Shapely. When I try to ...
3
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1answer
192 views

Is there an online reference available for the Fiona and Shapely libraries?

Is there an online reference available for the Fiona and Shapely libraries? I'm thinking a real reference, beside the tutorial-style documentation: http://toblerity.github.io/shapely/manual.html ...
2
votes
1answer
55 views

how to differentiate between common parts of the triangle and extract linestring from it

Can you help me break down shape A to different linestrings: lines 2 & 3 AND line 1? The shape contains three different polygons (A, B, C). I wish to determine the start/end point of each part ...
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0answers
221 views

Install shapely for QGIS on Mac

I know there are a number of similar questions, but none of them have answers that allow me to use shapely in QGIS. In particular I am trying to install the Contour plugin, but this fails with the ...
0
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2answers
130 views

Why is Shapely not installing correctly?

I am trying to run Shapely on a new machine, and tried both installing it from source, using the installer on its webpage, and using pip install shapely. Every reference I try to make from the library ...
0
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2answers
403 views

How to install Shapely, but got stuck into Python language

I have a MAC OSX 10.7.5 and am trying to learn how to use QGIS. Following a couple of tutorials I came to know I have to install shapely. I followed the instructions by the multi-cited ...
4
votes
2answers
118 views

Install Shapely with GEOS on heroku

I have a web mapping app running on Heroku. My app is written in python. Using pip I was able to install various pure python libraries that were needed. I would now like to install Shapely too. ...
5
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2answers
771 views

Python: How to export Shapely objects to DXF file

Using shapely package for Python how to export the resulting shapely objects such as buffer to a DXF file?
5
votes
5answers
1k views

Python, shapely library: is it possible to do an affine operation on shape polygon?

I am trying to create a rotated rectangle in lat/lon coordinates. Basically I have the coordinates of the center and rotation angle around the center. Is it possible to do using, shapely or gdal, or ...
7
votes
2answers
711 views

Converting KML files for use with Python library Shapely

I am trying to get a KML-file (wijken.kml) into Shapely. The KML-file is validated against the proper XML schema, so I guess the input is correct. Routes I have tried: 1) Converting to WKT or WKB ...
1
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0answers
130 views

Why does polygon.intersection(complex_linestring) split the linestring and mess up Z?

I have a complex (self crossing) line with Z values which I'd like to truncate to the area inside a box. The problem is Shapely splits the line into simple (non-crossing) sections and the Z value at ...
1
vote
1answer
173 views

How to set the path to shapely?

I am using QGIS 1.8.0 on Mac OS 10.8.3 with python 2.7. Thanks to other threads in the forum, I have successfully installed shapely here: ...
7
votes
1answer
308 views

Is there a significantly faster way to buffer than arcmap?

I hope this question is appropriate here and I apologize if it is more of a discussion question than a specific technical problem. I have to buffer 150,000 polygons for a real estate project. While ...
9
votes
4answers
5k views

using shapely: translating between Polygons and MultiPolygons

[EDIT: the solution to this was simply to use OGR to read shapefiles. See geographika's example.] In an ESRI shapefile, there is no distinction between Polygons and MultiPolygons. Furthermore, there ...
1
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1answer
914 views

QGIS Python version

I have brewed python 2.7.3 onto my Mac (Lion), and installed shapely via pip install shapely. The Polygonizer plugin, however, does not find the shapely library. I see when QGIS loads a Python ...
3
votes
0answers
216 views

Importing matplotlib basemap and shapely

I'm not sure if this is the right place to ask this, but here we go. I have a python script that uses matplotlib's basemap and another part that uses shapely to do an intersection of 2 polygons. If ...
3
votes
1answer
605 views

Does anyone have a shapely install for python “dummies” guide?

I have read both questions in regard to installing shapely on a Mac (OS Mountain Lion) and haven't been able to figure it out. I'm not familiar with python syntax and am just trying to get shapely ...
0
votes
2answers
565 views

Python module “shapely.wkb” missing

I am trying to follow a tutorial from here http://qgistips.spatialthoughts.com/2012/12/find-neighbor-polygons-in-layer-in-qgis.html#more I have downloaded the relevant python script and edited it as ...
3
votes
2answers
400 views

Checking if a point is in a circle

I'm using shapely to check if a point is in a polygon, but I also need to check if a point is in a circle. Checking the docs, I don't see how do that... Maybe I could create a circle? circle = ...
5
votes
1answer
228 views

How do you fix Overlapping Lines?

I have a line dataset that contains some lines where the "end points" are actually found in the middle of the line. In the image below, the nodes are shown in green and one of the end points in red. ...