Do calculations for certain hours in a 3D array

I have a 3D array with 30x50x8760. 30x50 is values from measurements. 8760 is measurements for every hour in one year. I also have a 8760x1 datetime array shown in, dd-MMM-yyyy HH:mm:ss. I want to do some calculations like f.eks the mean. There will be calculations for certain hours like 08:00:00, 09:00:00, 10:00:00 etc. How can I do this? The only way I know is to first make a 2D array from the 3D array, and make a table from the two arrays.

Answer 1

[Rik]

You can use the hour function to get the submatrix with logical indexing.

temp=A(:,:,hour(date_vec)==8);
mean_val=sum(sum(temp,1),2)/(size(A,1)*size(A,2));