Read equations from a text file and create a cell array in MATLAB

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Hello everybody! I have a text file with 8000 equations and I want to create a cell array of 8000x1 for the equations as strings. I have considered textscan for this purpose, but all the equations doesn't have same number of variables and hence I cannot specify the number of columns. How do I go about it? Example:
equations.txt:
1. a=b+c
2. d=e+f+g+h
3. y=2+x*z
  4 Comments
Tiasa Ghosh
Tiasa Ghosh on 7 May 2018
the line numbers are not present in the file. I wrote them just to number the equations. the equations ma contain special characters too.

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Accepted Answer

Walter Roberson
Walter Roberson on 7 May 2018
Provided there are no UNICODE or UTF-8 characters in the file:
filename = 'equations.txt';
S = fileread(filename);
equations = regexp(S, '\r?\n', 'split');
if isempty(equations{end}); equations(end) = []; end %last entry is often empty due to the way regexp split works
If the file does include Unicode that is UTF encoded, then potentially more steps would need to be used to read it properly.

More Answers (1)

Ameer Hamza
Ameer Hamza on 7 May 2018
Edited: Ameer Hamza on 7 May 2018
The following lines will read the lines from the text file and return a cell array of function handles
f = fopen('test.txt');
q = textscan(f, '%s');
fclose(f);
funHandles = cell(1, length(q{1}));
for i=1:length(q{1})
splitAtEqualSign = strsplit(q{1}{i}, '=');
rhs = splitAtEqualSign{2};
funHandles{i} = matlabFunction(str2sym(rhs));
end
  3 Comments
Ameer Hamza
Ameer Hamza on 7 May 2018
Since you mentioned that line numbers are not present. I have updated the answer.

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