weighted-randoms ( length histogram -- seq )


Vocabulary
math.extras

Inputs
lengthan object
histograman object


Outputs
seqan object


Definition
USING: assocs kernel math math.statistics namespaces random
sequences sorting.extras ;

IN: math.extras

: weighted-randoms ( length histogram -- seq )
unzip cum-sum swap
[ [ last >float random-generator get ] keep ] dip
[ [ [ random* ] 2curry ] dip [ bisect-left ] curry compose ]
dip [ nth ] curry compose replicate ;