How to change cell arrays to 3D arrays in order to speed up calculations?

Hello, For example I have two cell arrays x {10}(20x5) non integer values and k {10}(5x1) integer values 1:5, and use one cell array as index to other array.

x1=cellfun(@(x,y) x(5,y),x,k, 'UniformOutput',false);

and result is x1 {10}(1x5), unfortunately cell fun is slow with gpuArray when working with bigger arrays, what would be the way to use 3D arrays and maybe arrayfun for this?

[Guillaume]

Mantas Vaitonis's comment mistakenly posted as an answer moved here:

An example would be if

x(:,:,1)
1 8 10 2 5
3 5 7 9 11
4 5 2 3 7
12 10 4 6 2
9 7 10 1 3
.....
and k(:,:,1)
3
4
1
5
3
then x1(:,:1) would be
10 1 9 3 10

Answer 1

[KL]

Convert x into a 3d matrix using

 x_mat = cat(3,x{:});

and then if you want to extract 5th row from all the pages,

 x_mat(5,:,:)  %squeeze(x_mat(5,:,:)) , if you want a 2D matrix

[Mantas Vaitonis]

It is not that only 5th row is needed, but columns indexes should be taken from k {10}(5x1) where integer values from 1 to 5, that x(5,k(:,1,:),:).