How to add a phase shift of x, to a matrix of phase values that go from -180 to 180?

I have a matrix of phase values, that span from -180 to 180, computed with atan2d, from a set of imaginaries and reals. How do I introduce a phase shift to the phases?

Thank you

[Jan]

A samll example would reveal, what you expect as result. I'm not sure what "introduce a pahse shift" exactly means. So please edit your question and insert more details.