Given an unconstrained optimal assignment, enforce a constraint on it.

[jdmoorman]

Given an unconstrained optimal assignment, enforce a constraint on it.

[jdmoorman]

Talk to thomas about this. Might be too hard or spacially inefficient to do.

[qinyichen]

There are two functionalities needed:

(1) Fix a particular assignment (by setting the off entries in the same row/column of local costs to infinity), then update the global costs. Ideally this would be very fast if that assignment was part of the unconstrained least cost assignment.

(2) Suppose we know only certain rows of the local costs have changed, and others have not. And we want to update all the global costs based on this, ideally faster than if we assume all rows of the local costs changed.