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You'd be better off using the builtin "isinstance" function, e.g.: isinstance(x, int). This also has the added benefit of working nicely with inheritance (isinstance returns true if the actual type is derived from the classinfo passed as the second argument). See https://docs.python.org/3/library/functions.html#isinstance for details. Regards, Nathan On Fri, Jul 7, 2017 at 2:04 AM, Peter Otten <__peter__ at web.de> wrote: > Sayth Renshaw wrote: > > > I was trying to solve a problem and cannot determine how to filter 0's > but > > not false. > > > > Given a list like this > > ["a",0,0,"b",None,"c","d",0,1,False,0,1,0,3,[],0,1,9,0,0,{},0,0,9] > > > > I want to be able to return this list > > ["a","b",None,"c","d",1,False,1,3,[],1,9,{},9,0,0,0,0,0,0,0,0,0,0] > > > > However if I filter like this > > > > def move_zeros(array): > > l1 = [v for v in array if v != 0] > > l2 = [v for v in array if v == 0] > > return l1 + l2 > > > > I get this > > ['a', 'b', None, 'c', 'd', 1, 1, 3, [], 1, 9, {}, 9, 0, 0, 0, False, 0, > 0, > > [0, 0, 0, 0, 0] > > > > I have tried or conditions of v == False etc but then the 0's being false > > also aren't moved. How can you check this at once? > > > > > > Cheers > > > > Sayth > > Another option is to test for type(value) == int: > > >>> before = ["a",0,0,"b",None,"c","d",0,1,False,0,1,0,3,[],0,1,9,0,0, > {},0,0,9] > >>> wanted = ["a","b",None,"c","d",1,False,1,3,[],1,9, > {},9,0,0,0,0,0,0,0,0,0,0] > >>> after = sorted(before, key=lambda x: x == 0 and type(x) == int) > >>> assert str(after) == str(wanted) > >>> after > ['a', 'b', None, 'c', 'd', 1, False, 1, 3, [], 1, 9, {}, 9, 0, 0, 0, 0, 0, > 0, 0, 0, 0, 0] > > > That way float values will be left alone, too: > > >>> sorted([0.0, 0, False, [], "x"], key=lambda x: x == 0 and type(x) == > int) > [0.0, False, [], 'x', 0] > > > -- > https://mail.python.org/mailman/listinfo/python-list >

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