Converint between Cell arrays and Numbers and Strings

Hello,

I am trying to convert a double cell array as shown to individual 8 bit cells. (I hope I have been able to frame the question correctly, if not please take a look at my screenshot)

I want to convert each contents to individual bits, like for e.g [10000111] to individual 1 0 0 0 0 1 1 1

I have tried everything from cell2num, mat2cell, cell arrays and all but keep getting errors.

Please help me in solving this; also a little background theory on what these types of cells and 'cellarrays' mean would be a great help for next time!

Thanks,

Cheers,

kash022

[madhan ravi]

Result=cellfun(@(x) x-'0',string(yourcellarray),'un',0)

[Stephen23]

"Converint between Cell arrays and Numbers and Strings"

"I am trying to convert a double cell array as shown..."

Nothing in your screenshot is related to cell arrays:

https://www.mathworks.com/help/matlab/cell-arrays.html

Nothing in your question is related to string arrays:

https://www.mathworks.com/help/matlab/matlab_prog/create-string-arrays.html

After using MATLAB for more than two years it would be a good idea to learn what the basic data classes are and how to identify them:

https://www.mathworks.com/help/matlab/matlab_prog/fundamental-matlab-classes.html

"also a little background theory on what these types of cells and 'cellarrays' mean would be a great help for next time!"

Why not try reading the MATLAB documentation?:

https://www.mathworks.com/help/matlab/cell-arrays.html

PS: this is not twitter. Please do not put ugly # symbols at the start of each tag.

Answer 1

[Jan]

This obtains the digits of a decimal number:

x = 10000111;
n = floor(log10(x));
out = rem(floor(x(:) ./ power(10, n:-1:0)), 10)

>> [1 0 0 0 0 1 1 1]

I prefer this instead of the indirection of letting sprintf convert the number to a char vector and converting it back to a number.

"Cell arrays" are arrays of the class cell. These are array, which can contain elements of different sizes and classes. See:

doc cell

Example:

C = {[], 1, 1:2, 1:3, 'And a char vector also'}

If you want to store the output in one array and do not want leading zeros, you need a cell array, because the vectors have dirrent length.

x = [1, 101, 10000111];

C    = cell(size(x));
nMax = floor(log10(max(x)));
P    = power(10, nMax:-1:0);  % Expensive power operation once only
for k = 1:numel(x)
    n    = floor(log10(x(k)));
    C{k} = rem(floor(x(k) ./ P(nMax-n+1:end)), 10);
end

Note: You are working with Matlab since at least March 2016. You are expected to be able to read the documentation of the cell command.

[Kash022]

Thanks Jan for the detailed answers! Yes, I will take care to read the doucmentation in further details.

[Kash022]

@Jan what happens if I need leading zeros?

[Jan]

Leading zeros allow a simpler code:

x = 10000111;
n = floor(log10(max(x)));  % Here the maximum value matters
out = rem(floor(x(:) ./ power(10, n:-1:0)), 10)

Answer 2

[per isakson]

"cell array as shown" The screenshot doesn't show any cell array

Another approach

>> str = sprintf('%d', 10000111 ); 
>> num = reshape( sscanf( str, '%1d' ), 1,[] )
num =
     1     0     0     0     0     1     1     1
>> 

[Jan]

Easier:

str = sprintf('%d', 10000111 ) - '0'

[per isakson]

Easier to type, but it's too much black magic to my taste.

[Jan]

Exploiting the old-fashioned ASCII coding is less magic than calling sprintf, which is a huge library function. In very old Matlab versions, sprintf suffered from a bug, which allowed to gain admin privileges only by using strange format strings.

[per isakson]

>> '€'+'ab'     % undocumented behaviour(?)
ans =
        8461        8462
>> "€"+"ab"     % documented behaviour
ans = 
    "€ab"

Answer 3

[Walter Roberson]

I do not think you have a cell array at present. I think you have a double array.

OutputCell = arrayfun(@(V) sprintf('%08d', V) - '0'), YourArrayNameGoesHere, 'uniform', 0)

[Kash022]

sorry..this doesn't work..it outputs [1,0,1,0,1,0,0,1] which is not what I want...

it should be like [1] [0] [1] [0] [1] [0] [0] [1]

[Kash022]

well, it works like this now

my_cell = cell2mat(OutputCell);