# coxDegrees -- Computes the degree of a polynomial in the Cox ring corresponding to a section of a bundle on the scroll

## Synopsis

• Usage:
coxDegrees(ab,e)
• Inputs:
• ab, a list, containing the twist $a$ of the hyperplane class and $b$ of the ruling
• e, a list, the type of the scroll
• Outputs:
• ab', a list, containing the bidegree in the Cox ring

## Description

This function computes integers a' and b' such that $H^0(O_{P(E)}(aH+bR))$ corresponds to basis($\{a',b'\}$,S), where S is the Cox ring of the scroll $P(E)$.