How can I concatenate only the contents of the cells in a cell array whose length is more than a specific number?

I have a cell array (r) as given below.

r{1,1} = [1 2]
r{1,2} = 1x15 double which is like [3 4 ......17]
r{1,3} = [18 19]
r{1,4} = 1x16 double which is [20 21 ......35]
r{1,5} = 1x5 double [36 37 38 39 40]

it goes on till

r{31,1} = [107 108 109];

How can I concatenate only the contents of the cells whose length is more than 4? My output should be a single array which looks like [3 4 5..........17 20 21 ....35 36 37 38 39 40.....] Only the cells which have more than 4 elements should get concatenated.

Thanks in advance

Answer 1

[Geoff Hayes]

Quicklearner - iterate over each element in the cell array and check its length. If greater than four, then concatenate it with the other like data arrays. Something like

 data = [];
 for k=1:size(r,2)
     temp = r{1,k};
     if length(temp)>4
         data = [data temp];
     end
 end

Try the above and see what happens!

[quicklearner]

Hello, Thanks a lot for your answer, I had an error with my account and was not able to login. Apologise for the late acknowledgement. Cheers. Quicklearner.

Answer 2

[Sean de Wolski]

One liner

Rcat = [R{cellfun(@length,R)>4}];