optimize lack of redistribution in some denudation models

[jhidding]

the redistribution function now returns zero arrays which is a waste of energy.

possible solutions:

• return nothing instead, and deal with those in the model code
• redesign so that redistribution is never called on these models

[xyl96]

Have done this. Do I need to add a test for this and make sure when it encounters nothing it's indeed not assigning space for nothing?

[jhidding]

Let's look at that tomorrow. I'll be in the office.

[jhidding]

Btw, I can't see your solution. Could you create a branch and PR? You can use the button 'develop' here on the right.

No matter, found it!

[xyl96]

Btw, I can't see your solution. Could you create a branch and PR? You can use the button 'develop' here on the right.

No matter, found it!

I created a branch called issue/50, should I PR rn?