<vose> ( dist -- vose )

Vocabulary

math.extras

Inputs

dist

an object

Outputs

vose

an object

Definition

USING: arrays assocs kernel math math.vectors sequences ;

IN: math.extras

:: <vose> ( dist -- vose )
    V{ } clone :> small
    V{ } clone :> large dist assoc-size :> n n f <array>
    :> alias dist unzip dup [ length ] [ sum ] bi /f v*n
    :> ( items probs ) probs
    [ swap 1.0 < small large ? push ] each-index
    [ small empty? large empty? or ] [
        small pop :> s large pop :> l l s alias set-nth
        l dup probs [ s probs nth + 1 - dup ] change-nth 1.0 <
        small large ? push
    ] until 1.0 large [ probs set-nth ] with each 1.0 small
    [ probs set-nth ] with each n items probs alias vose boa ;