(gini) ( seq -- x )

Vocabulary

math.extras.private

Inputs

seq

an object

Outputs

x

an object

Definition

USING: math math.extras sequences sorting ;

IN: math.extras.private

:: (gini) ( seq -- x )
    seq sort :> sorted seq length :> len sorted 0
    [ + ] cum-reduce :> ( a b ) b len a * / :> c 1 len recip +
    2 c * - ;