How to make a equilateral triangular piece in a rectangular meshgrid?

How can I make a triangular meshgrid from rectangular meshgrid? I want to plot some equations that are obtained in a equilateral triangular shape (Like plotting in a rectangular shape using 'meshgrid').

Answer 1

[Mike Garrity]

Meshgrid is going to create a rectangular mesh, but you can fill the parts you don't want with nan, as I described in this post .