Falling

@staticmethod
def evaluate(waveform: WaveformVariable) -> float:
    """
    Calculate the falling edge of a waveform. Errors if image or scalar provided.

    First, applies smoothing by taking weighted nearest and next-nearest
    neighbour contributions to  y values whose difference from their neighbours
    is more than 0.2 times the total range in y. The global maximum y value is then
    identified along with the first x position to the right of the peak where the y
    value is less than or equal to half the global maximum. If all values of y to
    the right of the peak are greater than half the global maximum, the position of
    the global maximum is used. The value of x at this position is returned."
    """
    _, half_max_right = Builtin.calculate_fwhm(waveform)
    return half_max_right