Mean value of array

Chihiro Omori (view profile)

on 12 Apr 2019
Latest activity Edited by Guillaume

on 12 Apr 2019

Guillaume (view profile)

I need to calculate the mean of [1 2 ; 9 10],[2 3 ; 10 11] [3 4 ; 11 12] ,[4 5 ; 12 13] ....and make 3*7 matrix of the mean values of A(=4*8 matrix).
Does anyone has idea how to make it?
A=[1 2 3 4 5 6 7 8 ;
9 10 11 12 13 14 15 16;
17 18 19 20 21 22 23 24;
25 26 27 28 29 30 31 32]

Alex Mcaulley

Alex Mcaulley (view profile)

on 12 Apr 2019
The question is not clear. Can you show an example of input and the desired output?
Chihiro Omori

Chihiro Omori (view profile)

on 12 Apr 2019
I would like the output below.
A_mean = [5.5, 6.5, 7.5, 8.5, 9.5, 10.5, 11.5;
13.5 14.5, 15.5, 16.5, 17.5, 18.5, 19.5;
21.5, 22.5, 23.5, 24.5, 25.5, 26.5, 27.5]
The first row represents that ... 5.5 = ((1+2+9+10)/4) , 6.5 = ((2+3+10+11)/4), ...
The second row represents ... 13.5 = ((9+10+17+18)/4), ......
Guillaume

Guillaume (view profile)

on 12 Apr 2019
You've been given two methods to achieve that output.

Guillaume (view profile)

on 12 Apr 2019
Edited by Guillaume

Guillaume (view profile)

on 12 Apr 2019

Trivially solved with a convolution
A=[1 2 3 4 5 6 7 8 ;
9 10 11 12 13 14 15 16;
17 18 19 20 21 22 23 24;
25 26 27 28 29 30 31 32]
conv2(A, ones(2)/4, 'valid') %comvolve with [0.25, 0.25; 0.25, 0.25]

on 12 Apr 2019

Alex Mcaulley

on 12 Apr 2019
+1