node-red-contrib-tak-registration
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A Node-RED node to register to TAK and to help wrap files as datapackages to send to TAK
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TypeScript
import { FeatureCollection, Feature, Point, Position } from "@turf/helpers";
/**
* Takes a {@link FeatureCollection} of points and calculates the median center,
* algorithimically. The median center is understood as the point that is
* requires the least total travel from all other points.
*
* Turfjs has four different functions for calculating the center of a set of
* data. Each is useful depending on circumstance.
*
* `@turf/center` finds the simple center of a dataset, by finding the
* midpoint between the extents of the data. That is, it divides in half the
* farthest east and farthest west point as well as the farthest north and
* farthest south.
*
* `@turf/center-of-mass` imagines that the dataset is a sheet of paper.
* The center of mass is where the sheet would balance on a fingertip.
*
* `@turf/center-mean` takes the averages of all the coordinates and
* produces a value that respects that. Unlike `@turf/center`, it is
* sensitive to clusters and outliers. It lands in the statistical middle of a
* dataset, not the geographical. It can also be weighted, meaning certain
* points are more important than others.
*
* `@turf/center-median` takes the mean center and tries to find, iteratively,
* a new point that requires the least amount of travel from all the points in
* the dataset. It is not as sensitive to outliers as `@turf/center-mean`, but it is
* attracted to clustered data. It, too, can be weighted.
*
* **Bibliography**
*
* Harold W. Kuhn and Robert E. Kuenne, “An Efficient Algorithm for the
* Numerical Solution of the Generalized Weber Problem in Spatial
* Economics,” _Journal of Regional Science_ 4, no. 2 (1962): 21–33,
* doi:{@link https://doi.org/10.1111/j.1467-9787.1962.tb00902.x}.
*
* James E. Burt, Gerald M. Barber, and David L. Rigby, _Elementary
* Statistics for Geographers_, 3rd ed., New York: The Guilford
* Press, 2009, 150–151.
*
* @name centerMedian
* @param {FeatureCollection<any>} features Any GeoJSON Feature Collection
* @param {Object} [options={}] Optional parameters
* @param {string} [options.weight] the property name used to weight the center
* @param {number} [options.tolerance=0.001] the difference in distance between candidate medians at which point the algorighim stops iterating.
* @param {number} [options.counter=10] how many attempts to find the median, should the tolerance be insufficient.
* @returns {Feature<Point>} The median center of the collection
* @example
* var points = turf.points([[0, 0], [1, 0], [0, 1], [5, 8]]);
* var medianCenter = turf.centerMedian(points);
*
* //addToMap
* var addToMap = [points, medianCenter]
*/
declare function centerMedian(features: FeatureCollection<any>, options?: {
weight?: string;
tolerance?: number;
counter?: number;
}): Feature<Point, {
medianCandidates: Array<Position>;
[key: string]: any;
}>;
export default centerMedian;