double_logistic_derivative2 = (t, asymptote, time1, time2, rate1, rate2, level1, level2) => {
const denom = 1 + Math.exp(-rate1 * (t - time1)) + Math.exp(-rate2 * (t - time2));
return asymptote * (
2 * Math.pow((-Math.exp(-rate1 * (t - time1)) * rate1 - Math.exp(-rate2 * (t - time2)) * rate2), 2) / Math.pow(denom, 3)
- (Math.exp(-rate1 * (t - time1)) * Math.pow(rate1, 2) + Math.exp(-rate2 * (t - time2)) * Math.pow(rate2, 2)) / Math.pow(denom, 2)
);
}