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import jenksBreaks from "./jenks_breaks.js";import jenksMatrices from "./jenks_matrices.js";
/** * The **[jenks natural breaks optimization](http://en.wikipedia.org/wiki/Jenks_natural_breaks_optimization)** * is an algorithm commonly used in cartography and visualization to decide * upon groupings of data values that minimize variance within themselves * and maximize variation between themselves. * * For instance, cartographers often use jenks in order to choose which * values are assigned to which colors in a [choropleth](https://en.wikipedia.org/wiki/Choropleth_map) * map. * * @param {Array<number>} data input data, as an array of number values * @param {number} nClasses number of desired classes * @returns {Array<number>} array of class break positions * // split data into 3 break points * jenks([1, 2, 4, 5, 7, 9, 10, 20], 3) // = [1, 7, 20, 20] */function jenks(data, nClasses) {    if (nClasses > data.length) {        return null;    }
    // sort data in numerical order, since this is expected    // by the matrices function    data = data.slice().sort(function (a, b) {        return a - b;    });
    // get our basic matrices    const matrices = jenksMatrices(data, nClasses);    // we only need lower class limits here    const lowerClassLimits = matrices.lowerClassLimits;
    // extract nClasses out of the computed matrices    return jenksBreaks(data, lowerClassLimits, nClasses);}
export default jenks;