On 19/08/2011 20:55, ru...@yahoo.com wrote:
On 08/19/2011 11:33 AM, Matt Funk wrote:
On Friday, August 19, 2011, Alain Ketterlin wrote:
Matt Funk<matze...@gmail.com> writes:
thanks for the suggestion. I guess i had found another way around the
problem as well. But i really wanted to match the line exactly and i
wanted to know why it doesn't work. That is less for the purpose of
getting the thing to work but more because it greatly annoys me off that
i can't figure out why it doesn't work. I.e. why the expression is not
matches {32} times. I just don't get it.
Because a line is not 32 times a number, it is a number followed by 31
times "a space followed by a number". Using Jason's regexp, you can
build the regexp step by step:
number = r"\d\.\d+e\+\d+"
numbersequence = r"%s( %s){31}" % (number,number)
That didn't work either. Using the (modified (where the (.+) matches the end of
the line)) expression as:
number = r"\d\.\d+e\+\d+"
numbersequence = r"%s( %s){31}(.+)" % (number,number)
instance_linetype_pattern = re.compile(numbersequence)
The results obtained are:
results:
[(' 2.199000e+01', ' : (instance: 0)\t:\tsome description')]
so this matches the last number plus the string at the end of the line, but no
retaining the previous numbers.
The secret is buried very unobtrusively in the re docs,
where it has caught me out in the past. Specifically
in the docs for re.group():
"If a group is contained in a part of the pattern that
matched multiple times, the last match is returned."
[snip]
There's a regex implementation on PyPI:
http://pypi.python.org/pypi/regex
which does support capturing all of the matches of a group.
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