How to find average of every 1024th row in a vector of 61441 rows? The result should be a 60 x 1 matrix.

%The Vector name is fx. I want to convert a 61441 x 1 matrix to 60 x 1 matrix such that each value in new matrix is average of 1024 rows in original matrix.

Answer 1

[chicken vector]

Have a look at reshape and mean.

Answer 2

[Venkat Siddarth]

Hi @Rishi,

From the context,I understand that you want to convert a 61441x1 matrix to 60x1 matrix,such that each value is a mean of 1024 rows,here assuming that number of elements is 61440 but not 61441 since it is not a multiple of 1024 ,this can be solved as follows:

% create a sample 61440 x 1 matrix
fx = rand(61440, 1);
size(fx)

ans = 1×2

61440 1

% reshape the matrix into a 1024 x 60 x 1 matrix
fx_reshape = reshape(fx, 1024, 60, []);
size(fx_reshape)

ans = 1×2

1024 60

% take the mean of each 1024 x 60 slice along the first dimension
fx_mean = mean(fx_reshape, 1);
size(fx_mean)

ans = 1×2

1 60

% reshape the resulting 1 x 60 x 1 matrix into a 60 x 1 matrix
fx_final = reshape(fx_mean, [], 1);
size(fx_final)

ans = 1×2

60 1

I hope this resolves your query,

Regards

Venkat Siddarth V