MATLAB Answers

Reshaping a Char Array

3 views (last 30 days)
Jack Gallahan
Jack Gallahan on 16 Oct 2020
Commented: Jack Gallahan on 17 Oct 2020
Hi,
I am currently working on a Project where I need to order a Char Array like shown below
A = ['12';'12';'12';'12';'12';'12';'12';'12';'34';'34';'34';'34';'34';'34';'34';'34';'56';'56';'56';'56';'56';'56';'56';'56';'78';'78';'78';'78';'78';'78';'78';'78';'AA';'AA';'AA';'AA';'AA';'AA';'AA';'AA';'BB';'BB';'BB';'BB';'BB';'BB';'BB';'BB';'CC';'CC';'CC';'CC';'CC';'CC';'CC';'CC';'DD';'DD';'DD';'DD';'DD';'DD';'DD';'DD'];
I want to re-arrange the char array like:
'1234'
'1234'
'1234'
'1234'
'1234'
'1234'
'1234'
'1234'
'5678'
'5678'
'5678'
'5678'
'5678'
'5678'
'5678'
'5678'
'AABB'
'AABB'
'AABB'
'AABB'
'AABB'
'AABB'
'AABB'
'AABB'
'CCDD'
'CCDD'
'CCDD'
'CCDD'
'CCDD'
'CCDD'
'CCDD'
'CCDD'
What is the best way to do that? I tried using reshape function but it doesn't seem to work for this case?
Thanks in advance.

  0 Comments

Sign in to comment.

Accepted Answer

Rik
Rik on 16 Oct 2020
This should do it:
A = ['12';'12';'12';'12';'12';'12';'12';'12';'34';'34';'34';'34';'34';'34';'34';'34';'56';'56';'56';'56';'56';'56';'56';'56';'78';'78';'78';'78';'78';'78';'78';'78';'AA';'AA';'AA';'AA';'AA';'AA';'AA';'AA';'BB';'BB';'BB';'BB';'BB';'BB';'BB';'BB';'CC';'CC';'CC';'CC';'CC';'CC';'CC';'CC';'DD';'DD';'DD';'DD';'DD';'DD';'DD';'DD'];
B=mat2cell(A,ones(size(A,1),1),2);
B=reshape(B,8,[]);
part1=B(:,1:2:end);part1=part1(:);
part2=B(:,2:2:end);part2=part2(:);
B=cell2mat([part1 part2]);

  1 Comment

Jack Gallahan
Jack Gallahan on 17 Oct 2020
Also is this the most efficient way to do this?
Because I have 134,217,728 Bytes each is 2 chars converting mat2cell and back takes to much time and memory. Sometimes matlab gives Out of Memory error. Is there another way?

Sign in to comment.

More Answers (1)

Ameer Hamza
Ameer Hamza on 16 Oct 2020
Something like this
A = ['12';'12';'12';'12';'12';'12';'12';'12';'34';'34';'34';'34';'34';'34';'34';'34';'56';'56';'56';'56';'56';'56';'56';'56';'78';'78';'78';'78';'78';'78';'78';'78';'AA';'AA';'AA';'AA';'AA';'AA';'AA';'AA';'BB';'BB';'BB';'BB';'BB';'BB';'BB';'BB';'CC';'CC';'CC';'CC';'CC';'CC';'CC';'CC';'DD';'DD';'DD';'DD';'DD';'DD';'DD';'DD'];
idx = find([1; diff(A(:,1))]);
B = reshape(string(A), diff(idx(1:2)), []);
B = B(:,1:2:end) + B(:,2:2:end);
B = char(B(:));

  6 Comments

Show 3 older comments
Rik
Rik on 16 Oct 2020
Have you seen my answer below? This answer can also be modified for such cases, but mine would have an obvious parameter to edit.
Ameer Hamza
Ameer Hamza on 17 Oct 2020
It appears to be working in that case too
A = [repmat('12', 256, 1); repmat('34', 256, 1); repmat('56', 256, 1); repmat('78', 256, 1); repmat('AA', 256, 1); repmat('BB', 256, 1); repmat('CC', 256, 1); repmat('DD', 256, 1)];
idx = find([1; diff(A(:,1))]);
B = reshape(string(A), diff(idx(1:2)), []);
B = B(:,1:2:end) + B(:,2:2:end);
B = char(B(:));
The only case it will fail is if the second letter changes and the first letter remain same, for example
A = ['12';'12';'14';'14';'56';'56';'78';'78';'AA';'AA';'BB';'BB';'CC';'CC';'DD';'DD'];
In that case, following modification
idx = find([1; any(diff(A),2)]);
works, which is a more general form of the line in my answer and work for the original input too.
Jack Gallahan
Jack Gallahan on 17 Oct 2020
The problem is, original data is ADC values which varies continously thus I can not rely on value of first 4 bit and second 4 bit. Values might be '9C', '00','15','0E,'28'..... and so on. The numbers on my first post was just to show the placement of chars that is needed.

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by