# indie:lang_version = 5
from indie import indicator, format, param, source, band, color, level, line_style, plot
from indie.algorithms import Highest, Lowest
from indie.math import divide


@indicator('Williams %R', format=format.PRICE)  # Williams Percent Range
@param.int('length', default=14, min=1)
@param.source('src', default=source.CLOSE, title='Source')
@band(-20, -80, line_color=color.GRAY, fill_color=color.PURPLE(0.1), title='Background')
@level(-50, line_color=color.GRAY, line_style=line_style.DOTTED, title='Middle Level')
@plot.line(color=color.PURPLE, title='%R')
def Main(self, length, src):
    max = Highest.new(self.high, length)[0]
    min = Lowest.new(self.low, length)[0]
    return 100 * divide(src[0] - max, max - min)