No. There isn't an increment_cell or equivalent message.

the loop with getcell is really simple, though.

It is, but then you're either incrementing every time you send a getcell, or you end up with a bunch of instances of the same matrix. Could put in a gate I suppose, but it just seems like too many objects for such a simple task. Maybe in Max7...

Use jit.expr to create the appropriate mask, and then add it to the original matrix using jit.op.

this is great, but can the value in the mask be changed through exper or is the output only boolean? I have this solution but seems a like a bit much.

I think this is a little closer to what you are looking for

Andrew's solution is simpler, without a doubt.

Here's the answer to your earlier question.

Ah great those are both much better :D