MATLAB Answers

Reading the required variables for a function

1 view (last 30 days)
Adam
Adam on 5 Nov 2013
Commented: Azzi Abdelmalek on 5 Nov 2013
Is there a function that will read the number and names of variables needed to run a function. I'm working on a brute force solution now that just opens the function as a text file and searches for the function declaration then reads the strings between the parenthesis.

  2 Comments

Azzi Abdelmalek
Azzi Abdelmalek on 5 Nov 2013
Do you want the number of variables or their names?
Adam
Adam on 5 Nov 2013
Both, your answer is a viable option, but I don't see how it will read the variables if the function call is not the first line of the .m file.

Sign in to comment.

Answers (3)

Azzi Abdelmalek
Azzi Abdelmalek on 5 Nov 2013
Edited: Azzi Abdelmalek on 5 Nov 2013
fid = fopen('file.m');
line=''
while isempty(line)
line=fgetl(fid)
end
fclose(fid);
v=regexp(line,'(?<=\().+(?=\))','match')
n=strfind(v{1},',') % number of variables
%If you want their names
w=regexp(v{1},',','split')

  6 Comments

Show 3 older comments
Azzi Abdelmalek
Azzi Abdelmalek on 5 Nov 2013
For comment we can add a test
if line(1)=='%'
line=''
end
Walter Roberson
Walter Roberson on 5 Nov 2013
Comments can start anywhere on a line. Also, blanks are permitted on lines.
line = regexprep(line, {'%.*', '^s+'}, {'', ''});
Azzi Abdelmalek
Azzi Abdelmalek on 5 Nov 2013
The first character of line is always different from ' '

Sign in to comment.



Adam
Adam on 5 Nov 2013
Edited: Adam on 5 Nov 2013
Thanks for the help Azzi. I never used the regexp function before. It works really well in this application.
function [nvars,vars] = req_variables(filename)
% % Open the file for reading only.
[fid,msg] = fopen(filename,'r');
if fid <= 0
disp('Was not able to open file');
disp(msg)
return;
end
% Read the file, line by line, until we find the function call
line = ' ';
while (~strcmp(line(1:8),'function'))
line = fgetl(fid);
end
% Read the variable names and number from the line
v=regexp(line,'(?<=\().+(?=\))','match');
nvars =strfind(v{1},','); % number of variables
vars=regexp(v{1},',','split');
%Close the file
fclose(fid);

  0 Comments

Sign in to comment.

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!