wwbsr/node_modules/highcharts/es-modules/Stock/Indicators/RSIIndicator.js

/* *
 *
 *  License: www.highcharts.com/license
 *
 *  !!!!!!! SOURCE GETS TRANSPILED BY TYPESCRIPT. EDIT TS FILE ONLY. !!!!!!!
 *
 * */
'use strict';
import U from '../../Core/Utilities.js';
var isArray = U.isArray, seriesType = U.seriesType;
/* eslint-disable require-jsdoc */
// Utils:
function toFixed(a, n) {
    return parseFloat(a.toFixed(n));
}
/* eslint-enable require-jsdoc */
/**
 * The RSI series type.
 *
 * @private
 * @class
 * @name Highcharts.seriesTypes.rsi
 *
 * @augments Highcharts.Series
 */
seriesType('rsi', 'sma', 
/**
 * Relative strength index (RSI) technical indicator. This series
 * requires the `linkedTo` option to be set and should be loaded after
 * the `stock/indicators/indicators.js` file.
 *
 * @sample stock/indicators/rsi
 *         RSI indicator
 *
 * @extends      plotOptions.sma
 * @since        6.0.0
 * @product      highstock
 * @requires     stock/indicators/indicators
 * @requires     stock/indicators/rsi
 * @optionparent plotOptions.rsi
 */
{
    /**
     * @excluding index
     */
    params: {
        period: 14,
        /**
         * Number of maximum decimals that are used in RSI calculations.
         */
        decimals: 4
    }
}, 
/**
 * @lends Highcharts.Series#
 */
{
    getValues: function (series, params) {
        var period = params.period, xVal = series.xData, yVal = series.yData, yValLen = yVal ? yVal.length : 0, decimals = params.decimals, 
        // RSI starts calculations from the second point
        // Cause we need to calculate change between two points
        range = 1, RSI = [], xData = [], yData = [], index = 3, gain = 0, loss = 0, RSIPoint, change, avgGain, avgLoss, i;
        // RSI requires close value
        if ((xVal.length < period) || !isArray(yVal[0]) ||
            yVal[0].length !== 4) {
            return;
        }
        // Calculate changes for first N points
        while (range < period) {
            change = toFixed(yVal[range][index] - yVal[range - 1][index], decimals);
            if (change > 0) {
                gain += change;
            }
            else {
                loss += Math.abs(change);
            }
            range++;
        }
        // Average for first n-1 points:
        avgGain = toFixed(gain / (period - 1), decimals);
        avgLoss = toFixed(loss / (period - 1), decimals);
        for (i = range; i < yValLen; i++) {
            change = toFixed(yVal[i][index] - yVal[i - 1][index], decimals);
            if (change > 0) {
                gain = change;
                loss = 0;
            }
            else {
                gain = 0;
                loss = Math.abs(change);
            }
            // Calculate smoothed averages, RS, RSI values:
            avgGain = toFixed((avgGain * (period - 1) + gain) / period, decimals);
            avgLoss = toFixed((avgLoss * (period - 1) + loss) / period, decimals);
            // If average-loss is equal zero, then by definition RSI is set
            // to 100:
            if (avgLoss === 0) {
                RSIPoint = 100;
                // If average-gain is equal zero, then by definition RSI is set
                // to 0:
            }
            else if (avgGain === 0) {
                RSIPoint = 0;
            }
            else {
                RSIPoint = toFixed(100 - (100 / (1 + (avgGain / avgLoss))), decimals);
            }
            RSI.push([xVal[i], RSIPoint]);
            xData.push(xVal[i]);
            yData.push(RSIPoint);
        }
        return {
            values: RSI,
            xData: xData,
            yData: yData
        };
    }
});
/**
 * A `RSI` series. If the [type](#series.rsi.type) option is not
 * specified, it is inherited from [chart.type](#chart.type).
 *
 * @extends   series,plotOptions.rsi
 * @since     6.0.0
 * @product   highstock
 * @excluding dataParser, dataURL
 * @requires  stock/indicators/indicators
 * @requires  stock/indicators/rsi
 * @apioption series.rsi
 */
''; // to include the above in the js output