MATLAB: Ignoring comments when parsing

fileprogramming

I am currently parsing a file using the following scheme.

fmt = '%s%s';
opt = {'Delimiter','='};
[fid,msg]=fopen(file,'rt');
assert(fid>=3,msg);
C = textscan(fid,fmt,opt{:});
fclose(fid);

However, this is unable to ignore comments. If the file I am parsing has some commented lines, how can I skip those?

Thanks!

Best Answer

textscan() has a 'CommentStyle' option. See <https://www.mathworks.com/help/matlab/ref/textscan.html#btghhyz-1_sep_shared-CommentStyle>

For example, specify a character such as '%' to ignore text following the symbol on the same line. Specify a cell array of two character vectors, such as {'/*','*/'}, to ignore any text between those sequences.

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Use textscan and set the Delimiter and EndOfLine options, e.g.:

opt = {'Delimiter','\t', 'EndOfLine',';'};
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 0.46800   0.85200   0.15900   0.84600   0.74800

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Assuming no trailing newline characters in the files, perhaps one of these:

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st2 = fileread('file2.dat');
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