readtable error after r2014a --> r2022b upgrade

I have a script coded in MATLAB R2014a, running correctly. After intalling R2022b or later this line

t = readtable('test.txt', 'Delimiter',';');

results in error:

Delimiter must be a string array, character vector, or cell array of character vectors.

Why?

(t=readtable('test.txt') also causes this error.)

[Walter Roberson]

It seems likely to me that you have some third-party function with the same name as a Mathworks function, and that third-party function is interfering with parsing the delimiter.

Unfortunately after a bunch of tracing, I do not see where in the internal code that the validity of the delimiter is tested, so I am not presently able to guess as to which third-party function might be involved.

I suggest to copy the data file into a new directory, and try the readtable() from that new directory; if it works then the problem is a third-party function in you previous current directory. If it does not work, then I would suggest experimenting with

restoredefaultpath; rehash toolboxcache

and seeing whether the readtable() works; if it does then the problem is with some third-party toolbox that you had on your path.

Answer 1

[Star Strider]

Try one of these —

t = readtable('test.txt', 'Delimiter',";");

or:

t = readtable('test.txt', 'Delimiter',{';'});

The only illustrations in the 2024b documentation use string, " " arrays, although creatiing a cell array (by enclosing the value in curly brackets {}) could also work.

[Dora]

I've tried before.

t = readtable('test.txt') results in same error.

[Star Strider]

It runs here without error —

T1 = array2table(randi(9,5,3))

T1 = 5x3 table
    Var1    Var2    Var3
    ____    ____    ____

     8       8       3  
     8       8       7  
     6       2       4  
     8       7       2  
     3       8       3  

writetable(T1, 'test.txt', 'Delimiter',';')

type('test.txt')

Var1;Var2;Var3
8;8;3
8;8;7
6;2;4
8;7;2
3;8;3

t = readtable('test.txt', 'Delimiter',';');
disp(t)

    Var1    Var2    Var3
    ____    ____    ____

     8       8       3  
     8       8       7  
     6       2       4  
     8       7       2  
     3       8       3  

I seriously doubt that this is an inherent problem with R2022b itself, although your installation may be having problems.

You may need to Contact Support.

.