How to extract the first column of a structure array and save it as a different array

I have a structure array containing the names of my files in the first column.

I want to extract only the names of my files and store it in a different array.

I tried the following but it does not work:

% My struct array with 15560 elements where the name in the first column
files = dir('seaice_conc_daily_nh_*_v04r00*.nc');

%I tried this would work but it only returns the name of the first
%element...
filenames = files.name

%I know I can call individual elements i with:
filenames_i = files(i).name

%But I want a new array with all the name of my files

Thank you

[Stephen23]

"I have a structure array containing the names of my files in the first column."

Actually the names are stored in the field 'name'. The size of a structure is independent of how many fields it has:

https://www.mathworks.com/help/matlab/matlab_prog/create-a-structure-array.html

https://www.mathworks.com/help/matlab/matlab_prog/access-multiple-elements-of-a-nonscalar-struct-array.html

[A LL]

Good to know, thanks!

Answer 1

[Stephen23]

fnm = {files.name}

https://www.mathworks.com/help/matlab/matlab_prog/comma-separated-lists.html

https://www.mathworks.com/matlabcentral/answers/1656435-tutorial-comma-separated-lists-and-how-to-use-them

[A LL]

This is what I was looking for, thanks!

Answer 2

[Ruchika P Barman]

It is my understanding that you have a structure array containing the names of your files in the first column of the structure array and are trying to extract only the names of the files and store it in a different array. The following code should help you achieve the same.

filenames = vertcat(files.name)

[A LL]

Thank you for your answer.

This is not super convenient since it creates an array of size (length(files)) X (# of character in the name of the file). It stores each character of the name of the file in an individual character cell. I wanted to have an array of size (length(files)) X 1 with the name of the files in a single cell.

Answer 3

[Tasneem]

It is my understading that you are trying to extract first column from an array. so you could use files(:,1) to extract the first column and store the output in a different array.

The below is the code.

files = dir('seaice_conc_daily_nh_*_v04r00*.nc');
filenames = files(:,1);

[A LL]

Thank you for your answer. However, this command only creates the same structure array I had initially i.e. the first column is the name, the second is the folder, third is the date, fourth is the bytes and etc.