histogram.src.js 6.43 KB
/* *
 *
 *  Copyright (c) 2010-2017 Highsoft AS
 *  Author: Sebastian Domas
 *
 *  License: www.highcharts.com/license
 *
 *  !!!!!!! SOURCE GETS TRANSPILED BY TYPESCRIPT. EDIT TS FILE ONLY. !!!!!!!
 *
 * */
'use strict';
import H from '../parts/Globals.js';
import U from '../parts/Utilities.js';
var isNumber = U.isNumber, objectEach = U.objectEach;
import derivedSeriesMixin from '../mixins/derived-series.js';
var seriesType = H.seriesType, correctFloat = H.correctFloat, arrayMax = H.arrayMax, arrayMin = H.arrayMin, merge = H.merge;
/* ************************************************************************** *
 *  HISTOGRAM
 * ************************************************************************** */
/**
 * A dictionary with formulas for calculating number of bins based on the
 * base series
 **/
var binsNumberFormulas = {
    'square-root': function (baseSeries) {
        return Math.ceil(Math.sqrt(baseSeries.options.data.length));
    },
    'sturges': function (baseSeries) {
        return Math.ceil(Math.log(baseSeries.options.data.length) * Math.LOG2E);
    },
    'rice': function (baseSeries) {
        return Math.ceil(2 * Math.pow(baseSeries.options.data.length, 1 / 3));
    }
};
/**
 * Returns a function for mapping number to the closed (right opened) bins
 * @private
 * @param {Array<number>} bins - Width of the bins
 * @return {Function}
 **/
function fitToBinLeftClosed(bins) {
    return function (y) {
        var i = 1;
        while (bins[i] <= y) {
            i++;
        }
        return bins[--i];
    };
}
/**
 * Histogram class
 * @private
 * @class
 * @name Highcharts.seriesTypes.histogram
 * @augments Highcharts.Series
 */
seriesType('histogram', 'column', 
/**
 * A histogram is a column series which represents the distribution of the
 * data set in the base series. Histogram splits data into bins and shows
 * their frequencies.
 *
 * @sample {highcharts} highcharts/demo/histogram/
 *         Histogram
 *
 * @extends      plotOptions.column
 * @excluding    boostThreshold, dragDrop, pointInterval, pointIntervalUnit,
 *               stacking
 * @product      highcharts
 * @since        6.0.0
 * @optionparent plotOptions.histogram
 */
{
    /**
     * A preferable number of bins. It is a suggestion, so a histogram may
     * have a different number of bins. By default it is set to the square
     * root of the base series' data length. Available options are:
     * `square-root`, `sturges`, `rice`. You can also define a function
     * which takes a `baseSeries` as a parameter and should return a
     * positive integer.
     *
     * @type {"square-root"|"sturges"|"rice"|number|function}
     */
    binsNumber: 'square-root',
    /**
     * Width of each bin. By default the bin's width is calculated as
     * `(max - min) / number of bins`. This option takes precedence over
     * [binsNumber](#plotOptions.histogram.binsNumber).
     *
     * @type {number}
     */
    binWidth: undefined,
    pointPadding: 0,
    groupPadding: 0,
    grouping: false,
    pointPlacement: 'between',
    tooltip: {
        headerFormat: '',
        pointFormat: ('<span style="font-size: 10px">{point.x} - {point.x2}' +
            '</span><br/>' +
            '<span style="color:{point.color}">\u25CF</span>' +
            ' {series.name} <b>{point.y}</b><br/>')
    }
}, merge(derivedSeriesMixin, {
    setDerivedData: function () {
        var yData = this.baseSeries.yData;
        if (!yData.length) {
            return;
        }
        var data = this.derivedData(yData, this.binsNumber(), this.options.binWidth);
        this.setData(data, false);
    },
    derivedData: function (baseData, binsNumber, binWidth) {
        var series = this, max = arrayMax(baseData), 
        // Float correction needed, because first frequency value is not
        // corrected when generating frequencies (within for loop).
        min = correctFloat(arrayMin(baseData)), frequencies = [], bins = {}, data = [], x, fitToBin;
        binWidth = series.binWidth = series.options.pointRange = (correctFloat(isNumber(binWidth) ?
            (binWidth || 1) :
            (max - min) / binsNumber));
        // If binWidth is 0 then max and min are equaled,
        // increment the x with some positive value to quit the loop
        for (x = min; 
        // This condition is needed because of the margin of error while
        // operating on decimal numbers. Without that, additional bin
        // was sometimes noticeable on the graph, because of too small
        // precision of float correction.
        x < max &&
            (series.userOptions.binWidth ||
                correctFloat(max - x) >= binWidth ||
                correctFloat(min + (frequencies.length * binWidth) - x) <= 0); x = correctFloat(x + binWidth)) {
            frequencies.push(x);
            bins[x] = 0;
        }
        if (bins[min] !== 0) {
            frequencies.push(correctFloat(min));
            bins[correctFloat(min)] = 0;
        }
        fitToBin = fitToBinLeftClosed(frequencies.map(function (elem) {
            return parseFloat(elem);
        }));
        baseData.forEach(function (y) {
            var x = correctFloat(fitToBin(y));
            bins[x]++;
        });
        objectEach(bins, function (frequency, x) {
            data.push({
                x: Number(x),
                y: frequency,
                x2: correctFloat(Number(x) + binWidth)
            });
        });
        data.sort(function (a, b) {
            return a.x - b.x;
        });
        return data;
    },
    binsNumber: function () {
        var binsNumberOption = this.options.binsNumber;
        var binsNumber = binsNumberFormulas[binsNumberOption] ||
            // #7457
            (typeof binsNumberOption === 'function' && binsNumberOption);
        return Math.ceil((binsNumber && binsNumber(this.baseSeries)) ||
            (isNumber(binsNumberOption) ?
                binsNumberOption :
                binsNumberFormulas['square-root'](this.baseSeries)));
    }
}));
/**
 * A `histogram` series. If the [type](#series.histogram.type) option is not
 * specified, it is inherited from [chart.type](#chart.type).
 *
 * @extends   series,plotOptions.histogram
 * @excluding data, dataParser, dataURL
 * @product   highcharts
 * @since     6.0.0
 * @apioption series.histogram
 */
/**
 * An integer identifying the index to use for the base series, or a string
 * representing the id of the series.
 *
 * @type      {number|string}
 * @apioption series.histogram.baseSeries
 */
''; // adds doclets above to transpiled file