MATLAB: How to “writetable” with a CSV file when table elements have newlines or double quotation marks

breakcsvdetectimportoptionsdouble-quoteslineMATLABquotequotestringreadtablewritetable

I have a table, "DataTable", in a MATLAB with elements that are strings containing line breaks, double quotes, and commas.
When I write the table from the CSV file, the table is not the same as the one I had originally.  I get extra rows where the line breaks were and the quotes are not how they were originally.
Why does this happen and how can I write my table using a CSV file?

Best Answer

Based on the definition of the CSV format, fields containing line breaks (CRLF), double quotes, and commas should be enclosed in double-quotes.
In order to write the original table to CSV format, you can add the "QuoteStrings" flag to "writetable".  The flag is documented at the link below:
https://www.mathworks.com/help/matlab/ref/writetable.html#input_argument_d0e1111341
This is illustrated as follows:
>> writetable(DataTable, 'DataTable.csv','QuoteStrings',true);
Then, when reading from the CSV, you should explicitly tell "readtable" the format of the file.  This option's workflow is documented at the link below:
https://www.mathworks.com/help/matlab/ref/readtable.html#bvghccx
This is illustrated as follows:
>> opts = detectImportOptions('DataTable.csv'); 
>> T = readtable('DataTable.csv',opts)
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