Get the percent of points under a line Python-CodePudding

I have this graph with a line that follows y = xfunction and shows points in there. Like in the following image:

My question is: Given n points in the graph (columns x and y), how can I get the percent of points below and above the line?

What I tried is this:

def function(df, y):
    total = len(df)
    count = (df[y] > df.index).sum()
    percent = (count*100)/total
    return percent

Where total is the total of points of a dataframe and count is the sum of all values of the column y greater than the index. That point of view is wrong.

What I want is, for example, given 10 points, says 70% of the points are below of the line and can count 7 points below the line.

CodePudding user response：

To get the percentage of points below the line, you can use

(df[y] <= df.index).mean() * 100

CodePudding user response：

Points below the line satisfy the equation x > y. So, the percentage is:

df[df.x > df.y].size / df[[x, y]].size * 100

CodePudding user response：

For a point to be below the line, its x coordinate must be greater than its y coordinate:

(df['x'] > df['y']).sum() / len(df) * 100

CodePudding user response：

The easiest way I know to do this is to use numpy's