r - data.table::fread and Unbalanced "

Question

When I tried to read a csv file using data.table:fread(fn, sep='', header=T), it gives an "Unbalanced " observed on this line" error. The data has 3 integer variables and 1 string variable. The strings in the csv file are not enclosed with ", and yes there are some lines that contains " within the string variable and the " characters are not in pairs.

I am wondering is it possible to let fread just ignore the unpaired " in the variable and continue reading data? Thanks.

Here is the sample data(just one record)

N_ID    VISIT_DATE  REQ_URL REQType
175931  2013-3-8 23:40:30   http://aaa.com/rest/api2.do?api=getSetMobileSession&data={"imei":"60893ZTE-CN13cd","appkey":"android_client","content":"Z0JiRA0qPFtWM3BYVltmcx5MWF9ZS0YLdW1ydXoqPycuJS8idXdlY3R0TGBtU   1

Answer 1

UPDATE: Now implemented in v1.8.11

From NEWS :

fread now accepts quotes (both ' and ") in the middle of fields, whether the field starts with " or not, rather than the 'unbalanced quotes' error, #2694. Thanks to baidao for reporting. It was known and documented at the top of ?fread (text now removed). If a field starts with " it must end with " (necessary if the field separator itself is in the field contents). Embedded quotes can be in column names too. Newlines ( ) still can't be in quoted fields or quoted column names, yet.

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Yes as @agstudy said, embedded quotes are a known documented problem not yet implemented since fread is new. Strictly speaking, I suppose these ones aren't embedded because the string in your example doesn't start with a quote, though.

Anyway, I've filed this as a bug report so it doesn't get forgotten. To be done in the next release. Thanks for highlighting.

#2694 : Strings including quotes but not starting with quote in fread