删除python文件中每行逗号前的所有字符

Question

I need a small function in python that would read in a file and then remove all the characters up to AND INCLUDING a comma character. so for instance the following two line file:

hello,my name is
john,john, mary

would be:

my name is
john, mary

Answer 1

You have been advised to use re.split() already; however, regular split() method of str should suffice as well:

with open('new_file', 'w') as f_out, open('my_file') as f_in:
    for line in f_in:
        new_str = ','.join(line.split(',')[1:])
        f_out.write(new_str)

Answer 2

What you want is called Regular Expressions . Specifically, the split should work well.

vals=re.split(',',string,1)

Answer 3

also:

line = 'hello,my name is'
line[line.find(',')+1 :  ]     #find position of first ',' and slice from there
>>> 'my name is'

Answer 4

Use partition

>>> foo = 'hello, my name is'
>>> foo.partition(',')[2]
' my name is'
>>> foo = 'john, john, mary'
>>> foo.partition(',')[2]
' john, mary'
>>> foo = 'test,'
>>> foo.partition(',')[2]
''
>>> foo = 'bar'
>>> foo.partition(',')[2]
''