"Not enough input arguments" error when using fullfile

Im trying to pull a couple different csv files from a folder on my computer. the code im using is directly copy and pasted from other code I have written and have never run into this issue, when I run the code I get the following error:

Error using fullfile (line 3)
Not enough input arguments.

Error in A20241203 (line 8)
F1 = fullfile(S1.folder,S1.name);

Heres the code I wrote to access and the folder and files I need to open. Its three csv files all with (7) in the name.

P = 'my directory';

S1 = dir(fullfile(P,'*(7)*.csv'));

F1 = fullfile(S1.folder,S1.name);

M1 = readmatrix(F1);

Again, ive never run into this issue before, when reading the documentation I dont see how I dont have enough input arguments? Thanks!

[Sandeep Mishra]

Hi @Bradley

Could you please confirm if you are in the same directory where the code previously worked? Also, what is the output of S1?

Answer 1

[Walter Roberson]

S1 = dir(fullfile(P,'*(7)*.csv'));

That is returning the empty result, because it cannot find the directory or cannot match *(7)*.csv files in that directory.

Answer 2

[Stephen23]

"I dont see how I dont have enough input arguments? "

Very easily, when S1 is empty:

S1 = dir('thisNameDoesNot*Exist')

S1 = 

  0x1 empty struct array with fields:

    name
    folder
    date
    bytes
    isdir
    datenum

F1 = fullfile(S1.folder,S1.name)

Error using fullfile (line 3)
Not enough input arguments.

Because your code is then exactly equivalent to calling this:

F1 = fullfile()

which clearly does not have any input arguments, thus the error.

Your usage of FULLFILE would also be incorrect when S1 has multiple elements.

In fact, the only time your code would work properly is when S1 is scalar. Which is unlikely to be useful.

Explanation of why this happens: https://www.mathworks.com/matlabcentral/discussions/tips/847976-tutorial-comma-separated-lists-and-how-to-use-them

Solution

I suspect that what you intended to write was this, with cell arrays as inputs to FULLFILE:

F1 = fullfile({S1.folder},{S1.name})
%             ^         ^ ^       ^