Unrecognized function or variable 'readlines'?

Hi, I am attempting to run the following code to read in the attached text file "data settings XRE.txt. However, even though the file is on my matlab path, I get the error message below. I am running Matlab 2020a.

[file,path] = uigetfile('*.txt');
if isequal(file,0)
   disp('User selected Cancel');
else
   disp(['User selected ', fullfile(path,file)]);
end
% file = uigetfile('*.txt')
txt = readlines(fullfile(path,file));
[field,value] = arrayfun(@customFunction,txt);
% data = struct;

% for n = 1:numel(field)
%     data.(field(n)) = value(n);
% end

testStr='Ring level';
% Search for 1st occurence of 'testStr' in 'field'
k=find(field==testStr,1);
if not(isempty(k))
    A = value(k);
    disp([testStr,' =',num2str(value(k))])
end

testStr='x_end';
k=find(field==testStr,1);
if not(isempty(k))
    B = value(k);
    disp([testStr,' =',num2str(value(k))])
end

% data

function [f,v] = customFunction(str)
str = split(str,'=');
size(str);
f = strrep(deblank(str(1)),'"','');

if size(str,1) == 2
    v = str2double(strrep(deblank(str(2)),'"',''));
else
    v=NaN;
end
end

Unrecognized function or variable 'readlines'.

Error in Read_In_2 (line 21)

txt = readlines(fullfile(path,file));

Answer 1

[DGM]

It's not complaining about the txt file missing. It can't find readlines.m, because readlines() was introduced in R2020b. You just missed it ... or it missed you.

Finding an alternative really depends on what sort of stuff is in the file and how you're wanting to handle it.

[Ryan]

Okay, great. Thank you for the additional information.