On Thu, 15 Sep 2005, Reem Mohammed wrote:
> Suppose we have data file like this one (Consider all lines as strings )
>
> 1 2 3 3 4 4 4 4 5 6
> 2 2 2 5 5 5 6
> 3 2 1 1 1 3 3 3 4 6
>
> I would like to remove line if its belong to another one, and will be
> able to do this if longer line come after a short one.
when you say "belong to another one", do you mean "is a substring of
another one"? so 4 5 6 would belong to 1 2 3 4 5 6 7 8?
if so, what you're asking for is the set of upper bounds of a partially
ordered set. i often find that i need to compute things like this; i
haven't figured out a way to do it any faster than the obvious:
def upperbounds(set, order):
"""Finds the upper bounds of a set under a partial order.
Set is an iterable (which may contain duplicates - it doesn't actually
need to be a set), and order is a function of two arguments such that
order(a, b) returns True if a is greater than b, and False otherwise.
"""
bounds = [] # this would be better as a set, really
for item in set:
for bound in bounds:
if (order(bound, item)):
break
if (order(item, bound)):
bounds.remove(bound)
else:
bounds.append(item)
return bounds
you could use this as follows:
lines = map(str.strip, inputfile.readlines())
print upperbounds(lines, str.__contains__)
tom
--
I content myself with the Speculative part [...], I care not for the Practick.
I seldom bring any thing to use, 'tis not my way. Knowledge is my ultimate end.
-- Sir Nicholas Gimcrack
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