Function multifractal_spectrum 

pub fn multifractal_spectrum<T>(
    signal: &Signal<T>,
    wavelet: &dyn Wavelet,
    config: MultifractalConfig,
) -> Result<MultifractalSpectrum>
where
    T: SignalType + Float + FromPrimitive + AddAssign + SubAssign + MulAssign + DivAssign + 'static,