I have the lines from a CSV file:
315,"Misérables, Les (1995)",Drama|War
315,Big Bully (1996),Comedy|Drama
I want to split the line and make a list of 3 elements and I need a general REGEX expression that splits where it encounters ',' but since the title may have a comma (As shown in the first line), I need to skip the parsing of the title. A title that has commas has also quotation marks but I need the expression to work for both cases. Is it possible doing it with REGEX?
I'm trying to learn REGEX by myself and I'm having difficulties understanding some cases. I could really appreciate your help!
CodePudding user response：
If you're trying to parse a .csv file, don't do it by hand, Python already has loads of libraries that will do it for you.
Otherwise if your string has quotation marks when there is a comma inside the title, and doesn't have them when there is not, you can do it like this:
>>> x = '315,"Misérables, Les (1995)",Drama|War'
>>> y = '315,Big Bully (1996),Comedy|Drama'
>>> x
'315,"Misérables, Les (1995)",Drama|War'
>>> y
'315,Big Bully (1996),Comedy|Drama'
>>> x.split('"') if len(x.split('"')) == 3 else x.split(',')
['315,', 'Misérables, Les (1995)', ',Drama|War']
>>> y.split('"') if len(y.split('"')) == 3 else y.split(',')
['315', 'Big Bully (1996)', 'Comedy|Drama']
This leaves the comma inside the first and last part (if it's split by a quotation mark), so you will have to remove them afterwards manually.
CodePudding user response：
Actually, you do not need to use REGEX for this problem. QUOTING will solve this.
For example:
filereader = csv.reader(csv_input_file, delimiter=',', quotechar='"')
give it a try to solve your problem