Skip to main content

Geodesic Lines to GIS

https://travis-ci.org/GeographicaGS/GeodesicLinesToGIS.svg?branch=master

Computes geodesic lines from start point to end point and stores them in a GIS file (Shapefile and GeoJSON). A geodesic is the shortest path between two points on a curved surface, like an ellipsoid of revolution (Read more on Wikipedia).

This code is builded on top of three libraries: Pyproj, Fiona and Shapely.

There are several libraries to compute geodesic distances solving the geodesic inverse problem (to find the shortest path between two given points). I chose Pyproj because it works fine for this purpose and is an interface to a widely used library in the geospatial industry (Proj4 C library). Actually Proj4 C library (>= v.4.9.0) routines used to compute geodesic distance are a simple transcription from excellent Geographiclib C++ Library developed by Charles Karney. Proj4 C library < v.4.9.0 uses Paul D. Thomas algorithms. You can see more about this here: GeodeticMusings: a little benchmark of three Python libraries to compute geodesic distances.

All computations are performed with WGS84 ellipsoid and the CRS (Coordinate Reference System) of GIS file outputs are EPSG:4326.

In the examples section you can see the problem of calculating lines crossing antimeridian is solved.

Numpy array is supported as inputa data.

Geodesic lines examples

Below are shown different geodesic lines computed with this library on several map projections. Also you can see the relation with rhumb lines (loxodromic) and straight lines between the same points:

https://github.com/GeographicaGS/GeodesicLinesToGIS

Requirements

Usage

Usage is very simple. There are two modes: - Single input (one start/end). - Multiple input (more than one start/end).

Single input

Single input usage.

from geodesiclinestogis import GeodesicLine2Gisfile

lons_lats: input coordinates. (start longitude, start latitude, end longitude, end latitude)

lons_lats = (-3.6,40.5,-118.4,33.9)

Folder path to store output file and filename:

folderpath = '/tmp'

layername = "geodesicline"

Create object. You can pass two parameters: - antimeridian: [True, False] to solve antimeridian problem (default is True). - prints: [True, False] print output messages (default is True).

gtg = GeodesicLine2Gisfile()

Launch computations. You can pass two parameter: - lons_lats: input coords returned by gcComp. - km_pts: compute one point each n km (default is 20 km)

cd = gtg.gdlComp(lons_lats, km_pts=30)

Dump geodetic line coords to Linestring Feature and store in a GIS file.

Output formats: “ESRI Shapefile” (default), “GeoJSON”

# shapefile output
gtg.gdlToGisFile(cd, folderpath, layername)

# geojson output
gtg.gdlToGisFile(cd, folderpath, layername, fmt="GeoJSON")

Multiple input

Multiple input usage.

from geodesiclinestogis import GeodesicLine2Gisfile

data = [
        (-6.,37.,-145.,11.),
        (-150.,37.,140.,11.),
        (-6.,37.,120.,50.),
        (-3.6,40.5,-118.4,33.9),
        (-118.4,33.9,139.8,35.5),
        (-118.4,33.9,104.,1.35),
        (-118.4,33.9,151.,-33.9),
        (-20.4,33.9,178.,-33.9)
    ]

folderpath = "/tmp/geod_line"

layername = "geodesicline"

gtg = GeodesicLine2Gisfile()

gtg.gdlToGisFileMulti(data, folderpath, layername)

Numpy array (multiple) input

Numpy array input usage.

import numpy as np
from geodesiclinestogis import GeodesicLine2Gisfile

data_ = [
        (-6.,37.,-145.,11.),
        (-150.,37.,140.,11.),
        (-6.,37.,120.,50.),
        (-3.6,40.5,-118.4,33.9),
        (-118.4,33.9,139.8,35.5),
        (-118.4,33.9,104.,1.35),
        (-118.4,33.9,151.,-33.9),
        (-20.4,33.9,178.,-33.9)
    ]

data = np.array(data_)

folderpath = "/tmp/geod_line_np"

layername = "geodesicline"

gtg = GeodesicLine2Gisfile()

gtg.gdlToGisFileMulti(data, folderpath, layername)

About author

Developed by Cayetano Benavent. GIS Analyst at Geographica.

http://www.geographica.gs

License

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

Third-Party licenses

You can read Pyproj, Fiona and Shapely licenses in the next links: https://raw.githubusercontent.com/jswhit/pyproj/master/LICENSE https://raw.githubusercontent.com/Toblerity/Shapely/master/LICENSE.txt https://raw.githubusercontent.com/Toblerity/Fiona/master/LICENSE.txt

Metadata

Release files for GeodesicLinesToGIS 0.5.0

For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.

Source distribution (sdist)

Source distribution for GeodesicLinesToGIS 0.5.0
File Size Uploaded Provenance
GeodesicLinesToGIS-0.5.0.tar.gz 7.4 kB Without provenance Details

Release files / GeodesicLinesToGIS-0.5.0.tar.gz

Download URL GeodesicLinesToGIS-0.5.0.tar.gz
Size 7.4 kB
Tags Source
SHA-256 checksum
How to use checksums
d5af55b7610f80590a698009516f008294c5dafcbeca5c9dfc01d2343a073db5
BLAKE2b-256 checksum
How to use checksums
d5765953b9d899e8ebb100b1ee1e9db79063417be695e55c5edfdfaee6225751
Upload date
Uploaded using Trusted Publishing?
What is trusted publishing?
No

Security for GeodesicLinesToGIS 0.5.0

Provenance

Provenance describes where a file came from. On PyPI, provenance is shared via attestations, which provide a verifiable record of the build or publishing details. View details, limitations and caveats.

No provenance found

None of the files in this release were uploaded with provenance metadata.

A note on package security

PyPI is a repository for distributing packages, not a service for auditing them. While third-party security researchers and our staff do their best to detect and remove malicious packages, PyPI cannot guarantee the quality, security or suitability of any given package.

To learn more about protecting yourself from malicious actors, visit our package security documentation.

Anthropic, PBC Visionary sponsor Bloomberg Visionary sponsor Hudson River Trading Visionary sponsor Meta Visionary sponsor NVIDIA Visionary sponsor Microsoft Sustainability sponsor Depot Continuous Integration AWS Cloud computing and Security Sponsor Datadog Monitoring Fastly CDN Google Download Analytics Sentry Error logging StatusPage Status page