# Tagged Questions

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

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I'm using the world shape file that can be found at https://trac.openstreetmap.org/browser/applications/editors/merkaartor-branches/merkaartor-0.14-fixes/share/world_shp/world_adm0.shp?rev=17052. ...
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### How To Properly Implement a Bounding Box for Shapely & Fiona?

I am trying to spatially analyze two layers within same GDB file using Python / Shapely. Another user was kind enough to give me a procedure to go by in trying to reduce the number of senseless ...
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### How to simplify borders between polygons in shapely?

I have some fairly complex, and not completely accurate shapes stored as shapely Polygon objects. I'm trying to find the common borders, which should be as easy as finding the LineString returned from ...
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### How to find the area with most intersection for buffer regions?

Find the area with the most intersection This question relates to previous question asked - How to find the intersection areas of overlapping buffer zones in single shapefile?. I tried to find ...
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### Cut a linear feature according to the directions or azimuths

I have a shapefile linear that contains a single items as in the image and I want to divide it into several section respecting the azimuth and the line direction. i have this code : import os ...
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### Add attributes to an output shapefile schema (via meta)

I am trying to copy the schema of an existing shapefile and add to it in an output shapefile. Somehow I am not getting anywhere with this...though the docs seem very clear (and the download page : ...
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### 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 ...
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### Counting features into intersections of Shapely Polygons

I have a geopandas GeoDataFrame containing hundreds of shapely Polygon and MultiPolygon geometries. The polygons overlap in lots of places. I'd like to make a new geometry that contains a count of how ...
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### “Merging” 2 layers of LineString with splits at intersections

I would like to "merge" 2 networks of lines and these lines need to be split when they intersect. With pictures it should be clearer : What to do: if a black line intersects a red line, they ...
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### 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 ...
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### Interpolating every X distance along line in shapely

If I have a shapely multiline object that contains many lines whose total length each is 50km (when traced from the origin), and I want to interpolate along the multiline every X meters (let's say ...
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### Where is my Polygon?

I created this script to merge all of the polygons in a shapefile into a single polygon. I am using Python 2.7.5, Shapely 1.3.0, and Fiona 1.1.5. def merge(path_in, path_out): #Import Libraries ...
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### Find Properties of Nearest Line Segments to Point in Python

I have been trying to find a workable Python approach to finding nearest line segments to one (or more) points, and came accross @gene's solution to @RustyMagoo's problem here: from shapely.geometry ...
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### Spatially Analyzing two layers within same File Geodatabase using Python / Shapely?

I'm using a nested for-loop to do Shapely analysis between two Python lists created via two pre-reads of the same GDB file. One list contains all the features of a particular layer while the other ...
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### How do I create a raster file from a geopandas dataframe storing lats, longs, values, and geometries

From a text file with time, lat, long, and cf values, I create a pandas dataframe (cf_df). Then I use the lat, long values to create a geoseries and create a geopandas dataframe from the original ...
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### Projecting GeoJSON polygon object in python to calculate area

I have a script, written in python, that does many calculations - but one set of calculations hinges on determining the area of a polygon that I read in, in GeoJSON format. I can convert this object ...
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### Error and kernel dies with shapely/geos inside Jupyter notebook

I have a Python 2.7 script (code below) that scrapes data from a table on the web and draws a map. It runs fine from the command line using \$ python bears.py When I run the identical script from ...
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### Creating spatial layer from MS SQL Server table?

I have a table in MSSQL that I am trying to use to create a spatial layer from using the QgsVectorLayer function to load the table as a layer, and then using Fiona to create a shapefile but I am ...
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### Shapely's object.project method dealing with overlapping polyline

So I am interested in knowing how far along a polyline a given point sits. Python's shapely package has a method to do such a thing, see the below code: from shapely.geometry import LineString ip = ...
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### Point in Polygon using Rtree and Shapely

This is a repeat of my question over on StackOverflow. All, I am wondering what the correct syntax is for doing a point in polygon search using Shapely and RTree. I'm really interested in speeding ...
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### Reading/writing utf-8 encoded data using Fiona?

So I have a 'cpg' file with my 'in_file' shapefile data (definitely set to 'utf-8'). I was using 'meta' to create the same schema/crs as 'in_file'...though it runs, my text fields are borked on ...
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### Generate random points in polygon. Algorithm question

i created a Random Point Generator in python using the algorithm described here by @whuber. The algorithm is implemented using Shapely, PostGIS and psycopg2. To boost performance pythons ...
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### Adding a Property (attribute) to a geometry in Shapely/Fiona

Once you have line and polygon geometries, intersection using Shapely is very straight forward. What I did after that is to integrate all the looped 'intersected' geometries into a MultiLineString. ...
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### Point in Polygon operation for 100G of data

I have lat/lon point locations for over a billion points, all based in the US. For each point I would like to generate a dataset that links them to their county and to their MSA according to US Census ...
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### 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 X,...
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### 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 ...
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### 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 ...
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### How to do a Python / Fiona / Shapely equivalen to an ESRI ArcPy SpatialJoin?

I'm a GIS noob, but I am trying to learn as quickly as I can. Please bear with me. How can I identify what structures from one layer are WITHIN in some body of water in another layer? My problem ...
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### cartopy: plotting shapefiles

I am new to gis and am trying to plot a shapefile containing land polygons. (From OSM.) Unfortunately my output image is always empty (i.e. white). Can somebody tell me what I am doing wrong? import ...
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### Converting branched multiline into series of single lines in shapely

If I have a multiline string representing a branched network with a common starting point (red network in pic below): Does anyone know how to convert this to a set of individual single linestrings ...
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### Using shapely and geopandas in pyspark

I'm new to geospatial analysis and trying to start the analysis using python. Since the data is too huge we are trying to make use of hadoop and spark to get the analysis done. I would like to use ...
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### Calculating distances with lat/long in decimals and WGS 84

I need to calculate the distance between points of two different datasets, once with locations of towns, the other with locations of dams. Both are located in different countries in Africa. The more ...
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### Understanding output point in polygon solution?

My question refers to an old solution which is provided in How do I find out if a given lat lon is in a KML Linear ring using shapely? Using python3 I needed to update the code somewhat to get this ...
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### Finding common segments in Shapely LineStrings

I have two identically-sized collections of Shapely LineStrings, representing two sets of routes from a common origin to a set of common destinations. For each "pair" of routes (i.e. set_a[0], set_b[0]...