How To Calculate Parabolic SAR (Stop and Reverse) using TypeScript?

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function calculateSAR(data: number[], initialSAR: number, initialAF: number, maxAF: number): number[] {
    const sarValues: number[] = [];
    let EP = 0;
    let SAR = initialSAR;
    let AF = initialAF;

    for (let i = 1; i < data.length; i++) {
        if (SAR > data[i - 1]) {
            EP = Math.max(EP, data[i]);
            if (AF < maxAF) {
                AF += initialAF;
            }
        } else {
            EP = Math.min(EP, data[i]);
            if (AF < maxAF) {
                AF += initialAF;
            }
        }

        const newSAR = SAR + AF * (EP - SAR);

        // Check if SAR should reverse
        if (data[i] > data[i - 1]) {
            if (newSAR > data[i]) {
                newSAR = EP;
                AF = initialAF;
            }
        } else {
            if (newSAR < data[i]) {
                newSAR = EP;
                AF = initialAF;
            }
        }

        sarValues.push(newSAR);
        SAR = newSAR;
    }

    return sarValues;
}

// Example usage
const data = [10, 15, 20, 25, 20, 15, 10];
const initialSAR = 10;
const initialAF = 0.02;
const maxAF = 0.2;

const sarValues = calculateSAR(data, initialSAR, initialAF, maxAF);
console.log(sarValues);