(bigraded-ker/im-d) ( u-deg z-deg bigraded-basis -- null/rank )

Vocabulary

koszul

Inputs

u-deg	an object
z-deg	an object
bigraded-basis	an object

Outputs

null/rank

an object

Definition

USING: kernel math sequences ;

IN: koszul

: (bigraded-ker/im-d)
    ( u-deg z-deg bigraded-basis -- null/rank )
    [ ?nth ?nth ] 3keep [ [ 2 + ] dip 1 - ] dip ?nth ?nth
    dim-im/ker-d ;