How do I "writetable" with a CSV file when table elements have newlines or double quotation marks?

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?

Answer 1

[MathWorks Support Team]

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)