I am trying to parse about 20 million lines from a text file and am looking for a way to do some further manipulations on lines that do not start with question marks. I would like a solution that does not use regex matching. What I would like to do is something like this:
for line in x:
header = line.startswith('?')
if line.startswith() != header:
DO SOME STUFF HERE
I realize the startswith
method takes one argument, but is there any simple solution to get all lines from a line that DO NOT start with a question mark? Thanks in advance for the help.
Use generator expressions, the best way I think.
for line in (line for line in x if not line.startswith('?')):
DO_STUFF
Or your way:
for line in x:
if line.startswith("?"):
continue
DO_STUFF
Or:
for line in x:
if not line.startswith("?"):
DO_STUFF
It is really up to your programming style. I prefer the first one, but maybe second one seems simplier. But I don't really like third one because of a lot of indentation.