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- 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;
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