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About LinkBacksPradeep Jindal:
> Any comments?
Something with similar functionality (plus another 20 utility
functions/classes or so) has probably to go into the std lib... :-)
Bye,
bearophile
This is a discussion on Iterable Flattener with Depth. - Python ; Hi, 5 minute solution to one of my requirements. I wanted to flatten iterables upto a specific depth. To be true, didn't search for it on the internet prior to writing this one. def flatten_iter(my_iter, depth=None): """my_iter can be a ...
Iterable Flattener with Depth. Hi,
5 minute solution to one of my requirements. I wanted to flatten
iterables upto a specific depth.
To be true, didn't search for it on the internet prior to writing this one.
def flatten_iter(my_iter, depth=None):
"""my_iter can be a iterable except string containing nested
iterables upto any depth. This function will flat all
(except string) down to a list containing all the elements in
nested-order.
To add to it you can specify optional depth (int or long)
argument and the
function will flatten the iterable upto that depth (nesting).
"""
if not hasattr(my_iter, '__iter__') or isinstance(my_iter, basestring):
return [my_iter]
elif depth != None and depth <= 0:
return my_iter
temp = []
for x in my_iter:
temp.extend(flatten_iter(x, None if depth == None else depth-1))
return temp
py> temp = [1,[2,[3,4,5],'bash'],6,[7,[8,[9,10,['hi', 'hello']]]], 11, 12]
py> flatten_iter(temp,1)
[1, 2, [3, 4, 5], 'bash', 6, 7, [8, [9, 10, ['hi', 'hello']]], 11, 12]
py> flatten_iter(temp,2)
[1, 2, 3, 4, 5, 'bash', 6, 7, 8, [9, 10, ['hi', 'hello']], 11, 12]
py> flatten_iter(temp)
[1, 2, 3, 4, 5, 'bash', 6, 7, 8, 9, 10, 'hi', 'hello', 11, 12]
py> flatten_iter(temp,3)
[1, 2, 3, 4, 5, 'bash', 6, 7, 8, 9, 10, ['hi', 'hello'], 11, 12]
Any comments?
Thanks
- Pradeep
Re: Iterable Flattener with Depth. Pradeep Jindal:
> Any comments?
Something with similar functionality (plus another 20 utility
functions/classes or so) has probably to go into the std lib... :-)
Bye,
bearophile
Re: Iterable Flattener with Depth. On Nov 1, 5:03 pm, bearophileH...@lycos.com wrote:
> Pradeep Jindal:
>
> > Any comments?
>
> Something with similar functionality (plus another 20 utility
> functions/classes or so) has probably to go into the std lib... :-)
>
> Bye,
> bearophile
Same Here!
- Pradeep
Re: Iterable Flattener with Depth. On Nov 2, 6:32 am, praddy <praddyjin...@gmail.com> wrote:
> On Nov 1, 5:03 pm, bearophileH...@lycos.com wrote:
>
> > Pradeep Jindal:
>
> > > Any comments?
>
> > Something with similar functionality (plus another 20 utility
> > functions/classes or so) has probably to go into the std lib... :-)
>
> > Bye,
> > bearophile
>
> Same Here!
>
> - Pradeep
Yeah, everyone has to write a flatten sooner or later :-) My version
is at:
http://blog.tkbe.org/archive/python-flatten/
-- bjorn
Re: Iterable Flattener with Depth. thebjorn wrote:
> On Nov 2, 6:32 am, praddy <praddyjin...@gmail.com> wrote:
>> On Nov 1, 5:03 pm, bearophileH...@lycos.com wrote:
>>
>>> Pradeep Jindal:
>>>> Any comments?
>>> Something with similar functionality (plus another 20 utility
>>> functions/classes or so) has probably to go into the std lib... :-)
>>> Bye,
>>> bearophile
>> Same Here!
>>
>> - Pradeep
>
> Yeah, everyone has to write a flatten sooner or later :-) My version
> is at:
>
> http://blog.tkbe.org/archive/python-flatten/
>
> -- bjorn
>
And here is mine. Note that it is very similar to Michael Spencer's
implementation[1]. The only difference is that this adds a depth counter.
def iflat(itr, depth=0):
itr = iter(itr)
stack = []
cur_depth = 0
while True:
try:
elem = itr.next()
if hasattr(elem, "__iter__") and cur_depth < depth:
stack.append(itr)
itr = iter(elem)
cur_depth += 1
else:
yield elem
except StopIteration:
if not stack:
raise StopIteration
cur_depth -= 1
itr = stack.pop()
if __name__ == "__main__":
test1 = ((0, 1, 2), ((3, 4), 5), (((6, 7), 8), 9))
test2 = [1,[2,[3,4,5],'bash'],6,[7,[8,[9,10,['hi', 'hello']]]], 11, 12]
for x in (test1, test2):
print list(iflat(x))
print list(iflat(x, 1))
print list(iflat(x, 2))
print list(iflat(x, 3))
print list(iflat(x, 4))
print iflat(x, 10)
Ian
[1] http://mail.python.org/pipermail/pyt...ch/312022.html
Re: Iterable Flattener with Depth. On Friday 02 Nov 2007 10:43:45 pm Ian Clark wrote:
> thebjorn wrote:
> > On Nov 2, 6:32 am, praddy <praddyjin...@gmail.com> wrote:
> >> On Nov 1, 5:03 pm, bearophileH...@lycos.com wrote:
> >>> Pradeep Jindal:
> >>>> Any comments?
> >>>
> >>> Something with similar functionality (plus another 20 utility
> >>> functions/classes or so) has probably to go into the std lib... :-)
> >>> Bye,
> >>> bearophile
> >>
> >> Same Here!
> >>
> >> - Pradeep
> >
> > Yeah, everyone has to write a flatten sooner or later :-) My version
> > is at:
> >
> > http://blog.tkbe.org/archive/python-flatten/
> >
> > -- bjorn
>
> And here is mine. Note that it is very similar to Michael Spencer's
> implementation[1]. The only difference is that this adds a depth counter.
>
> def iflat(itr, depth=0):
> itr = iter(itr)
> stack = []
> cur_depth = 0
>
> while True:
> try:
> elem = itr.next()
> if hasattr(elem, "__iter__") and cur_depth < depth:
> stack.append(itr)
> itr = iter(elem)
> cur_depth += 1
> else:
> yield elem
> except StopIteration:
> if not stack:
> raise StopIteration
> cur_depth -= 1
> itr = stack.pop()
>
>
> if __name__ == "__main__":
> test1 = ((0, 1, 2), ((3, 4), 5), (((6, 7), 8), 9))
> test2 = [1,[2,[3,4,5],'bash'],6,[7,[8,[9,10,['hi', 'hello']]]], 11, 12]
>
> for x in (test1, test2):
> print list(iflat(x))
> print list(iflat(x, 1))
> print list(iflat(x, 2))
> print list(iflat(x, 3))
> print list(iflat(x, 4))
> print iflat(x, 10)
>
> Ian
>
> [1] http://mail.python.org/pipermail/pyt...ch/312022.html
Very nice non-recursive (iterative) implementation of the thing with required
features. Yours is double faster than mine if depth is not specified, Mine is
double faster than yours if depth is specified. And my main aim was the depth
thingy. What do you think?
- Pradeep