$$\frac{dy}{dx} = b\,(d - a)\,\exp(-b(x-c))\, u^{-1/g - 1} \quad\text{where } u = 1 + g\,\exp(-b(x-c))$$
Arguments
- x
Numeric vector. Independent variable (typically log10-concentration).
- a
Numeric scalar. Lower asymptote (baseline response).
- b
Numeric scalar. Scale parameter (\(b > 0\)); controls steepness.
- c
Numeric scalar. Inflection-point location on the x-axis.
- d
Numeric scalar. Upper asymptote (saturation response).
- g
Numeric scalar. Asymmetry (Richards) parameter (\(g > 0\)).
See also
Other derivatives:
dydx_gompertz4(),
dydx_logistic4(),
dydx_logistic5(),
dydx_loglogistic4()