Double summation of a matrix

How to implement the summation? I am not able to do this.

Answer 1

[Matt J]

In recent Matlab, you can do

sum(matrix,'all')

or more generally you can do

sum(matrix(:))

[Psk]

Then how will i specify the limits for summation?

[Rik]

Just an addition: Since R2018b you can use the S = sum(A,vecdim) syntax. So if you happen to have a 3D array and want to sum only rows and columns you can use this:

sum(matrix,[1 2])

[Matt J]

Then how will i specify the limits for summation?

You can extract the appropriate sub-matrix by indexing it, e.g.,

A=rand(10);

sum(A(1:5,2:7),'all')

ans = 14.8419

Answer 2

[Matt J]

The expression in your .jpg file, if it needs to be evaulated for all p,q would be

SML=conv2(ML,ones(N+1),'same')