33 lines
1023 B
JavaScript
33 lines
1023 B
JavaScript
/**
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* Indicator Definition Object for EMA.
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*/
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const EMA_INDICATOR = {
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name: 'EMA',
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label: 'Exponential Moving Average',
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usesBaseData: false, // This simple indicator uses the chart's currently displayed data
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params: [
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{ name: 'period', type: 'number', defaultValue: 20, min: 2 },
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],
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calculateFull: calculateFullEMA,
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};
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function calculateFullEMA(data, params) {
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const period = params.period;
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if (!data || data.length < period) return [];
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let emaData = [];
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const multiplier = 2 / (period + 1);
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let sum = 0;
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for (let i = 0; i < period; i++) {
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sum += data[i].close;
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}
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let prevEma = sum / period;
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emaData.push({ time: data[period - 1].time, value: prevEma });
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for (let i = period; i < data.length; i++) {
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const close = data[i].close;
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const ema = (close - prevEma) * multiplier + prevEma;
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emaData.push({ time: data[i].time, value: ema });
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prevEma = ema;
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}
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return emaData;
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}
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