Calculation the mean of a portion of a matrix

Hello!

I am having trouble finding out how can I calculate the mean of all the values in a 10x10 matrix (z) which do not lie along an edge of that same matrix (z)...

Thanks in advance!

Answer 1

[Matt J]

mean( z(2:end-1,2:end-1) ,'all')

[Moheb Amir Adel Kamel Rafla]

Thank you! I just got a little question, can you explain what does the 2:end-1 written twice between the , mean? (I just want to understand the logic of the whole command to be able to reproduce things that would be similair in the future), thanks again!

[Matt J]

You're quite welcome, but please Accept-click the answer to indicate that it does what you need.

The 2:end-1 is equivalent in this context to 2:10-1 or 2:9. It as as if you had written z(2:9,2:9). See also,

https://www.mathworks.com/help/matlab/ref/end.html#mw_9fea271b-869f-483f-b233-59caea76daf3

[Moheb Amir Adel Kamel Rafla]

Ah ok I get it! Thank you so much!