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searching lists for a string char

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Join Date: Oct 2009

Posts: 3

Reputation: plzhelp is an unknown quantity at this point

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plzhelp

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searching lists for a string char

22 Days Ago

is it possible to search a multi dimensional list for a certain letter then print out where that letter is?
i know u can use list.index() to find a letter but i could figure out how to do it with multi dimensional lists.

thx in advance

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Join Date: Jul 2008

Posts: 1,046

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jlm699

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Knows where his Towel is

21 Days Ago

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Originally Posted by plzhelp

is it possible to search a multi dimensional list for a certain letter then print out where that letter is?
i know u can use list.index() to find a letter but i could figure out how to do it with multi dimensional lists.

thx in advance

Something like this perhaps:

 Help with Code Tags 
 python Syntax (Toggle Plain Text) 
for idx_i, each_sublist in enumerate(main_object):
    for idx_j, each_string in enumerate(each_sublist):
        if each_string == my_letter:
            print 'Found %s at %s, %s' % (my_letter, idx_i, idx_j)
for idx_i, each_sublist in enumerate(main_object):
    for idx_j, each_string in enumerate(each_sublist):
        if each_string == my_letter:
            print 'Found %s at %s, %s' % (my_letter, idx_i, idx_j)

That could possibly work for you, otherwise you'll need to be a little more clear. Example input/output would help to define a way to solve this

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Join Date: Nov 2009

Posts: 79

Reputation: pythopian is an unknown quantity at this point

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pythopian

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Junior Poster in Training

A really quick hack for more than 2 dimensions

21 Days Ago

If you want to search sequences with more than 2 levels of nesting, you could do this:

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 Python Syntax (Toggle Plain Text) 
def deepfind(obj, test=lambda value: True):
    if not isinstance(obj, (list, tuple)):
        if test(obj):
            yield obj
    else:
        for each in obj:
            for found in deepfind(each, test):
                yield found
 
def test():
    data = [
        ['abc', 'def', 'geh'], [
            ['ijk', 'lmn', 'opq'],
            ['rst', 'uvw', 'xyz'],
            ],
        ]
    print list( deepfind(data, lambda value: 'a' in value or 'z' in value) )
 
>>> test()
['abc', 'xyz']
def deepfind(obj, test=lambda value: True):
    if not isinstance(obj, (list, tuple)):
        if test(obj):
            yield obj
    else:
        for each in obj:
            for found in deepfind(each, test):
                yield found

def test():
    data = [
        ['abc', 'def', 'geh'], [
            ['ijk', 'lmn', 'opq'],
            ['rst', 'uvw', 'xyz'],
            ],
        ]
    print list( deepfind(data, lambda value: 'a' in value or 'z' in value) )

>>> test()
['abc', 'xyz']

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