@showr/indicators/dist/ema/ema.js

Technical indicators for Trading made with Showr

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.EMA = void 0;
const core_1 = require("@showr/core");
const __1 = require("..");
class EMA extends core_1.Indicator {
    constructor(name = 'EMA', params) {
        super(name, function (dataset) {
            const { attribute, period = 5 } = params;
            const datasetLength = dataset.value.length;
            const _smoothing = 2 / (period + 1);
            const lastEMA = dataset.at(-2)?.getIndicator(this.name);
            if (lastEMA && !isNaN(lastEMA) && datasetLength > period) {
                const value = dataset.valueAt(-1, attribute);
                return value * _smoothing + lastEMA * (1 - _smoothing);
            }
            else {
                if (datasetLength === period) {
                    const sma = new __1.SMA('sma', { attribute, period });
                    return sma.calculate(dataset);
                }
                else {
                    if (datasetLength < period) {
                        return NaN;
                    }
                    else {
                        const dsSliced = new core_1.Dataset(dataset.value.slice(0, period));
                        const dsRemaining = new core_1.Dataset(dataset.value.slice(period));
                        this.spread(dsSliced);
                        dsRemaining.quotes.forEach((q) => dsSliced.add(q));
                        this.spread(dsSliced);
                        return dsSliced.at(-1).getIndicator(this.name);
                    }
                }
            }
        }, {
            params,
        });
    }
}
exports.EMA = EMA;