How to ignore values or set to NaN while keeping matrix same size?

I have a 2400 x 2400 matrix, 'alb_short', with values ranging from 1-100, but with many outliers over 100 which need to be ignored so I can plot the results.

How can I ignore these large values or set them to NaN so my matrix stays at its original 2400x2400 size?

Thank you.

Answer 1

[Azzi Abdelmalek]

A(A>100)=nan