Images of constructible sets

[Akhil Mathew]

Hello,

I am interested in computing the image of a constructible set under a
polynomial map, especially checking whether it is empty or not. Is
there a way to do this in Macaulay2?

Thanks!

Akhil Mathew

[Daniel R. Grayson]

The image of a nonempty set under a function is always a nonempty set,
so it seems that your question reduces to being able to tell whether a
constructible set is nonempty. Macaulay2 hasn't implemented the
notion of constructible set, but you can tell whether two closed
subsets have the same underlying sets of points by comparing the
radicals of their ideals, so you will be able to solve your problem.