error_bar: Draw an error bar to a plot
In m-Py/DOTA2: Discrete option test analysis

Draw an error bar to a plot

1 2	error_bar(x, y, upper, lower = upper, length = 0.1, width = 1.5, col = "black")

`x`	The x coordinates
`y`	The y coordinates
`upper`	The upper bound of the error interval (in relation to the y-coordinates)
`lower`	The lower bound of the error interval (in relation to the y-coordinates)
`length`	the width of the bar end
`width`	the width of the error bar line
`col`	The color of the error bar