how to get the key or values one by one from the dictionary?

Question

For example:

dictionary = {}
if x found in y:
    name = "simply"
    dictionary[name]={}
    bang = {'abc','dsw','lol'}
    dictionary[name]={bang}
for k in (dictionary):
    print (k)

what if i only want to get the first key 'abc' ?

what method should i use since print(k[0]) is not working for me. it will only print the 1st letter for all the keys

when i call dictionary["simply"] it will show

abc

dsw

lol

What if I only wan to get abc for further steps?

`set`s are "**Unordered** collections of unique elements". You cannot be sure what will you get as the "first" element. — Selcuk, Mar 10 '16 at 05:35

Apoorva Srivastava · Answer 1 · 2016-03-10T06:25:02.833

1

Python dictionaries are unordered. If you want an ordered dictionary, try OrderedDict.

>> from collections import OrderedDict
>> d = OrderedDict()    
>> d['apple'] = 'red'  
>> d['banana']='white'     
>> d.items()[0]

>> output: ('apple', 'red')

edited Mar 10 '16 at 06:25

answered Mar 10 '16 at 06:00

Apoorva Srivastava

388
2
19

He has a set not a dictionary! – schafle Mar 10 '16 at 06:09
NameError: name 'collections' is not defined How can I fix this? – Dsw Wds Mar 10 '16 at 06:13
Sorry, my bad. I edited the code, instead of writing collections.OrderedDict, simply write OrderedDict(). – Apoorva Srivastava Mar 10 '16 at 06:25
@wtpoo hey, your answer is correct, i can now do my jobs, thx, but why do u deleted it? – Dsw Wds Mar 10 '16 at 06:56
@Dsw Wds Cause you changed the question and my answer was no more relevant then – schafle Mar 10 '16 at 06:58

schafle · Accepted Answer · 2016-03-10T06:37:44.833

0

You are making a set and not a dictionary. If you do dir with your set, you can see that there's no way to get a certain key by name from set. So you have to use a non in-built collection.

>>> dictionary={'abc','dsw','lol'}
>>> type(dictionary)
<type 'set'>
>>> dir(dictionary)
['__and__', '__class__', '__cmp__', '__contains__', '__delattr__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__iand__', '__init__', '__ior__', '__isub__', '__iter__', '__ixor__', '__le__', '__len__', '__lt__', '__ne__', '__new__', '__or__', '__rand__', '__reduce__', '__reduce_ex__', '__repr__', '__ror__', '__rsub__', '__rxor__', '__setattr__', '__sizeof__', '__str__', '__sub__', '__subclasshook__', '__xor__', 'add', 'clear', 'copy', 'difference', 'difference_update', 'discard', 'intersection', 'intersection_update', 'isdisjoint', 'issubset', 'issuperset', 'pop', 'remove', 'symmetric_difference', 'symmetric_difference_update', 'union', 'update']
>>> dictionary.pop()
'dsw'
>>>

You can install ordered-set to do just that.

Do pip install ordered-set and then you can use it for your use case:

>>> from ordered_set import OrderedSet
>>> dir = OrderedSet(['abc','dsw','lol'])
>>> dir[0]
'abc'

edited Mar 10 '16 at 06:37

answered Mar 10 '16 at 05:36

schafle

615
4
10

So the result is not the "first" element. – Selcuk Mar 10 '16 at 05:38
pop removes an arbitrary element. OP Is asking for the first key, which is not possible to guarantee in a set. – idjaw Mar 10 '16 at 05:38
It is not the first one 'abc' .. it ais still random – Dsw Wds Mar 10 '16 at 06:34
Check now. When you create a dictionary the elements are unordered. So you have to give a list to ordered set so that it can maintain the order. – schafle Mar 10 '16 at 06:38
Dictionary **is** a dict in OPs code. bang is a set – MaxNoe Mar 10 '16 at 06:44
OP updated the question; earlier it was a set. :( – schafle Mar 10 '16 at 06:45
thanks ! your answer help ! – Dsw Wds Mar 10 '16 at 06:58

how to get the key or values one by one from the dictionary?

2 Answers2