How to change the 7th least significant of a binary code?

I had created a cell array of size <1x368cell>.

Each element of an array contains a binary code such as '11100101'.

I want to change the 7th bit of this code with an external value.

How could I do it?

Please help me.

Answer 1

[John BG]

Hi Himanshu Nailwal

binary codes can be represented with characters (translating numeric values with dec2bin) or also with logical values.

We can put logical values in cell fields in many different ways.

Since you haven not supplied the variable, let me start with

A={mod(dec2bin(randi([64 900],10,1)),2)}
A = 
    [10x10 double]

this could have been built in other ways. Now despite the Workspace Value reads 1x1 cell

A{1}

=
     0     1     0     0     0     1     1     0     0     1
     1     0     1     1     0     1     1     1     0     1
     0     1     1     0     1     0     1     0     0     1
     1     1     0     0     1     1     1     0     1     0
     0     0     1     1     0     1     1     0     0     0
     0     1     0     0     0     1     1     1     0     0
     0     0     1     0     1     1     1     0     0     1
     0     0     1     0     1     1     0     0     0     1
     1     1     0     0     0     1     0     1     1     1
     1     0     0     0     1     0     0     1     0     1

each code of yours is stored separately, not in char type, but logical bits.

To read one binary code

   A{1}(1,:)
   =
       0     1     0     0     0     1     1     0     0     1

to read 4 least significant bits

A{1}(1,[end-3:end])
 =
     1     0     0     1

to read a single bit, the first bit of the first code

A{1}(1,1)
=
     0

or the 8th bit of the 4th code

A{1}(4,8)
 =
     0

so, to access a particular bit across all codes,

   A{1}([1:end],4)
   =
       0
       1
       0
       0
       1
       0
       0
       0
       0
       0

if you find this answer useful would you please be so kind to mark my answer as Accepted Answer?

To any other reader, please if you find this answer of any help solving your question,

please click on the thumbs-up vote link,

appreciating time and attention

John BG

<mailto:[e-mail] [e-mail]>

Answer 2

[Walter Roberson]

T = cell2mat(YourCell(:));
T(:,7) = new values
NewCell = reshape( mat2cell(T, ones(1, size(T,1)), size(T,2)), 1, []);

[Himanshu Nailwal]

T = cell2mat(YourCell(:));
T(:,7) = 1
NewCell = reshape( mat2cell(T, ones(1, size(T,1)), size(T,2)), 1, []);

This gives an error and the output is as '1110011'.

How to correct it? Please help.

[Walter Roberson]

"new values" needs to be '1' not 1. You are not using numeric values for your representation: you are using the characters '0' and '1'

Answer 3

[Guillaume]

There are many ways:

for idx = 1:numel(yourcellarray)
   yourcellarray{idx}(7) = '1';
end
cellarrayaschar = char(yourcellarray);
cellarrayaschar(:, 7) = '1';
yourcellarray = cellstr(cellarrayaschar);
yourcellarray = cellfun(@(b) [b(1), '1', b(3:end)], yourcellarray, 'UniformOutput', false);

and more...