# indie:lang_version = 5
from math import isnan, pow
from indie import indicator, param, plot, color, MutSeriesF
from indie.algorithms import Ema
from indie.math import divide


@indicator('McGinley', overlay_main_pane=True)  # McGinley Dynamic
@param.int('length', default=14, min=1)
@plot.line(color=color.BLUE)
def Main(self, length):
    mg = MutSeriesF.new(init=0)
    if isnan(mg[1]):
        mg[0] = Ema.new(self.close, length)[0]
    else:
        mg[0] = mg[1] + divide(self.close[0] - mg[1], length * pow(divide(self.close[0], mg[1]), 4))
    return mg[0]