What is @turf/truncate?
@turf/truncate is a module in the Turf.js library that is used to truncate the precision of coordinates in GeoJSON data. This can be useful for reducing the size of GeoJSON files or for ensuring consistent precision across datasets.
What are @turf/truncate's main functionalities?
Truncate Coordinates
This feature allows you to truncate the coordinates of a GeoJSON object to a specified precision. In this example, the coordinates of a point are truncated to 3 decimal places.
const truncate = require('@turf/truncate');
const point = { "type": "Feature", "geometry": { "type": "Point", "coordinates": [70.123456789, 40.987654321] } };
const truncated = truncate(point, { precision: 3 });
console.log(truncated);
Truncate with Custom Options
This feature allows you to truncate the coordinates of a GeoJSON object with custom options. In this example, the coordinates of a LineString are truncated to 2 decimal places, and the number of coordinates is also limited to 2.
const truncate = require('@turf/truncate');
const lineString = { "type": "Feature", "geometry": { "type": "LineString", "coordinates": [[70.123456789, 40.987654321], [71.123456789, 41.987654321]] } };
const truncated = truncate(lineString, { precision: 2, coordinates: 2 });
console.log(truncated);
Other packages similar to @turf/truncate
geojson-precision
The geojson-precision package allows you to set the precision of GeoJSON coordinates. It is similar to @turf/truncate in that it helps reduce the size of GeoJSON files by limiting the number of decimal places in coordinates. However, it is a standalone package and not part of a larger geospatial library like Turf.js.
simplify-geojson
The simplify-geojson package is used to simplify GeoJSON geometries by reducing the number of points in the geometries. While it does not specifically truncate coordinate precision, it serves a similar purpose of reducing the size and complexity of GeoJSON data. It is more focused on simplifying shapes rather than just truncating coordinates.
@turf/truncate
truncate
Takes a GeoJSON Feature or FeatureCollection and truncates the precision of the geometry.
Parameters
geojson
GeoJSON any GeoJSON Feature, FeatureCollection, Geometry or GeometryCollection.options
Object Optional parameters (optional, default {}
)
options.precision
number coordinate decimal precision (optional, default 6
)options.coordinates
number maximum number of coordinates (primarly used to remove z coordinates) (optional, default 3
)options.mutate
boolean allows GeoJSON input to be mutated (significant performance increase if true) (optional, default false
)
Examples
var point = turf.point([
70.46923055566859,
58.11088890802906,
1508
]);
var options = {precision: 3, coordinates: 2};
var truncated = turf.truncate(point, options);
var addToMap = [truncated];
Returns GeoJSON layer with truncated geometry
This module is part of the Turfjs project, an open source
module collection dedicated to geographic algorithms. It is maintained in the
Turfjs/turf repository, where you can create
PRs and issues.
Installation
Install this module individually:
$ npm install @turf/truncate
Or install the Turf module that includes it as a function:
$ npm install @turf/turf
6.2.0
After a bit of hiatus, TurfJS is resuming releases.
⭐️ Major Updates
- ES Modules available for all packages
- Tree shaking should significantly reduce import size of @turf/turf
- Better support for ESM modules (PR https://github.com/Turfjs/turf/pull/1942 - Author @diachedelic)
- Clean-up of test and benchmark running to make publishing easier
- Enforce styling using Prettier
- Enable ESLint and get rid of unused variables
- Upgrade rollup for more correct javascript module builds
- Only include ES5 code
🚀 New Modules
[@turf/boolean-touches
][boolean-touches]
Determines if two features touch but do not intersect
[@turf/boolean-valid
][boolean-valid]
Checks if the geometry is a valid according to the OGC Simple Feature Specification
[@turf/quadrat-analysis
][quadrat-analysis]
Performs a quadrat analysis on a set of points
[@turf/rectangle-grid
][rectangle-grid]
Creates a grid of rectangles from a bounding box
[@turf/voroni
][voronoi]
Typescript types for the options parameter have been fixed
(PR https://github.com/Turfjs/turf/pull/1424 - Author @stevage)
[@turf/points-within-polygon
][points-within-polygon]
Typescript types around the Feature's Properties will now be preserved.
(PR https://github.com/Turfjs/turf/pull/1761 - Author @rugheid)
[@turf/rewind
][rewind]
Typescript types for the 'reverse' option are now correct. Previously it was misnamed as 'reversed'.
(PR https://github.com/Turfjs/turf/pull/1786 - Author @jonnycornwell)
[@turf/difference
][difference]
No longer publishes an .mjs file.
[@turf/meta
][meta]
No longer publishes an .mjs file.
[@turf/tag
][tag]
Add MultiPolygon support.
(PR https://github.com/Turfjs/turf/pull/1996 - Author bryceroney)
🐛 Bug Fixes
-
@turf/centroid
Don't visit first point twice when calculating centroid
(PR https://github.com/Turfjs/turf/pull/1894 - Author @rowanwins)
-
@turf/transform-translate
Better handling of negative distances
(PR https://github.com/Turfjs/turf/pull/1895 - Author @rowanwins)
-
@turf/union
, @turf/difference
, @turf/intersect
Use polygon-clipping library to fix correctness issues
(PR https://github.com/Turfjs/turf/pull/1916 - Authors @mbullington, @ngottlieb)
-
@turf/buffer
Change default number of steps to 8, and actually support the steps option
(PR https://github.com/Turfjs/turf/pull/1931 - Author stevenchanin)
-
@turf/buffer
Fix projection issues that produce undersized buffers at non-equatorial latitudes
(PR https://github.com/Turfjs/turf/pull/1956 - Author dyakovlev)
-
@turf/helpers
Add runtime checks to point() method, fixing an API break
(PR https://github.com/Turfjs/turf/pull/1964)
🏅 New Features/Enhancements
-
@turf/boolean-overlap
Better performance for MultiPoint geometries
(PR https://github.com/Turfjs/turf/pull/1910 - Author @mfedderly)
-
@turf/helpers
Add hectares to convertArea
(PR https://github.com/Turfjs/turf/pull/1943 - Author @DanielJDufour)
-
@turf/great-circle
Update Typescript types to support MultiLineString input
(PR https://github.com/Turfjs/turf/pull/1928 - Author kronick)
📖 Documentation
-
@turf/square-grid
Clarify inputs
(PR https://github.com/Turfjs/turf/pull/1885 - Author @raphael-leger)
-
@turf/greater-circle
Clarify properties option example
(PR https://github.com/Turfjs/turf/pull/1888 - Author @chris-catignani)
⚠️ Breaking Change
-
@turf/line-to-polygon
no longer modifies its input unless the mutate option is true
(PR https://github.com/Turfjs/turf/pull/1879 - Author @MortenBirk)
-
@turf/unkink-polygon
remove Number.prototype.modulo override
(PR https://github.com/Turfjs/turf/pull/1978)