function for cell array

Hi folks,

i´ve got a cell array with vectors of data type double in every cell. Now i want to apply a function to every single cell. I found the command cellfun(func,A) to be useful.

Nonetheless i dont know how to implement a function func to do what i want on every part of the cell array. In particular i dont get how to tell the function that the vectors of doubles in the cells of A are the input arguments.

I´m thankful for any advice!

Answer 1

[Jon]

Here's a simple example

% Make an example cell array with a vector in each cell
A = cell(2,3); % preallocate
for i = 1:2
    for j = 1:3
        A{i,j} = rand(4,1); 
    end
end
A

A = 2×3 cell array
    {4×1 double}    {4×1 double}    {4×1 double}
    {4×1 double}    {4×1 double}    {4×1 double}

% Now use cellfun to compute the sum of the elements in each vector
B = cellfun(@(x) sum(x),A)

B = 2×3

1.8600 1.9744 2.3527 2.2433 2.3225 2.4160

[Jon]

If you are still having trouble adapting this example to your situation, then please provide the details of the function that you would like to apply to each element of your cell array.

[Oskar Kilgus]

Thanks for the initial help Jon,

i guess the problem i´m dealing with is more about the function itself.

I´ve got a cell array with wave-data in every cell and want to apply the pitch function to it.

As mentioned above im struggling with the input for pitch. Lets take ur example:

% Make an example cell array with a vector in each cell
A = cell(2,3); % preallocate
for i = 1:2
    for j = 1:3
        A{i,j} = rand(4,1); 
    end
end
A

A = 2×3 cell array
    {4×1 double}    {4×1 double}    {4×1 double}
    {4×1 double}    {4×1 double}    {4×1 double}

The idea is now to do the following:

f0_A = cellfun(pitch(???),A)

I cant figure out how to tell the pitch function what the right input arguments are..

Thanks in advance!

[Jon]

I am not familiar with the "pitch" function, and it does not seem to be in my MATLAB R2022A, or any of my toolboxes. Maybe you have the Audio Toolbox? I see looking online that there is a pitch function in that toolbox https://www.mathworks.com/help/audio/ref/pitch.html#mw_cb9b23c6-9dfa-4f98-8596-743e701e5fb8. Assuming this is the function you are using and you have already defined the variable fs in your workspace, you could do something like:

f0_A = cellfun(@(x) pitch(x,fs),A)