Combining two different size variables into one matrix

Hi!

I have two variables of different size. Let's suppose A is the size of 1x5 and B is the size of 1x8. I want to make a matrix where the first row will be A, and the second raw will be B. The matrix should be the size of 2x8 where the last columns of the first row are replaced with NaNs. For example:

A = [1 2 3 4 5]

B = [1 2 3 4 5 6 7 8]

C = [1 2 3 4 5 NaN NaN NaN; 1 2 3 4 5 6 7 8]

How can I do this?

Thanks!

Answer 1

[Stephen23]

The simplest solution is to download this:

https://www.mathworks.com/matlabcentral/fileexchange/22909-padcat

and then all you need is this:

>> A = [1,2,3,4,5];
>> B = [1,2,3,4,5,6,7,8];
>> C = padcat(A,B)
C =
     1     2     3     4     5   NaN   NaN   NaN
     1     2     3     4     5     6     7     8

[Daria Ivanchenko]

Thank you very much! This function is awesome!

Answer 2

[Ameer Hamza]

Try this

A = [1 2 3 4 5];
B = [1 2 3 4 5 6 7 8];

M = {A, B}; % combine all variables in a cell array
n = max(cellfun(@numel, M));
M = cellfun(@(x) {[x nan(1,n-numel(x))]}, M(:));
C = cell2mat(M);

[Daria Ivanchenko]

Thanks!

And what if I want to combine vectors like:

A = [1 2 3 4 5 6 7 8; 1 2 3 4 5 NaN NaN NaN];
B = [1 2 3 4 5];
% to get a vector C like:
C = [1 2 3 4 5 6 7 8; 1 2 3 4 5 NaN NaN NaN; 1 2 3 4 5 NaN NaN NaN]

Is it somehow possible?

[Ameer Hamza]

My code works in this case too

A = [1 2 3 4 5 6 7 8; 1 2 3 4 5 NaN NaN NaN];
B = [1 2 3 4 5];

M = {A, B};
n = max(cellfun(@(x) size(x, 2), M));
M = cellfun(@(x) {[x nan(1,n-numel(x))]}, M(:));
C = cell2mat(M);

Result

>> C
C =
     1     2     3     4     5     6     7     8
     1     2     3     4     5   NaN   NaN   NaN
     1     2     3     4     5   NaN   NaN   NaN

[Daria Ivanchenko]

Thank you very much!