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From: Mark Lawrence <breamoreboy@yahoo.co.uk>
Subject: Re: How to select every other line from a text file?
Date: Mon, 13 Oct 2014 19:02:24 +0100
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On 13/10/2014 18:48, John Gordon wrote:
> In <3be64ca8-d2e7-493a-b4f3-ef114f581450@googlegroups.com> Rff <rwang@avnera.com> writes:
>
>> Hi,
>> I have a text file. Now it is required to select every other line of that
>> text to generate a new text file. I have read through Python grammar, but
>> still lack the idea at the beginning of the task. Could you tell me some
>> methods to get this?
>
> Initialize a counter variable to zero.  (Or one, depending if you want to
> select odd or even lines.)
>
> Each time you read a line from the file, add one to the counter.
>
> If the counter is odd, process the line; otherwise use the 'continue'
> statement to start the loop over and read another line.
>

Why bother to initialise a counter when you can get the enumerate 
function to do all the work for you?

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence