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Dictionary using variables as a keys - andresgt - Oct-05-2017
Im trying to create a dicctionary using two lists (one as a key and the other one as a value) like this:
list1 = ['A4', 'A9', 'A2'] # keys
list2 = [27.8, 7.1, 68.04] # values
Diccionary : {'A4': [27.8], 'A9': [7.1], 'A2': [68.04]}
Finally I need to sort by value and take the minimum value and key:
In this case: {'A9':[7.1]}
Thanks in advance
RE: Dictionary using variables as a keys - nilamo - Oct-05-2017
zip them, to create key-value pairs.
>>> keys = ['A4', 'A9', 'A2']
>>> values = [27.8, 7.1, 68.04]
>>> list(zip(keys, values))
[('A4', 27.8), ('A9', 7.1), ('A2', 68.04)]
>>> dict(zip(keys, values))
{'A9': 7.1, 'A4': 27.8, 'A2': 68.04}
>>>
RE: Dictionary using variables as a keys - miltmobley - Oct-09-2017
The solution above uses a dict, but does not sort on the values.
You can say:
>>> a=[1,2,3]
>>> b=[6,5,4]
>>> c=zip(a,b)
>>> c
[(1, 6), (2, 5), (3, 4)]
>>> d=sorted(c, key=lambda x: x[1]) # sort on value element
>>> d
[(3, 4), (2, 5), (1, 6)]
>>> e=dict(d)
>>> e
{1: 6, 2: 5, 3: 4}
RE: Dictionary using variables as a keys - nilamo - Oct-10-2017
(Oct-09-2017, 10:33 PM)miltmobley Wrote: >>> d
[(3, 4), (2, 5), (1, 6)]
>>> e=dict(d)
>>> e
{1: 6, 2: 5, 3: 4}Ok, but that's not sorted by value, either. And since dictionaries only maintain order in some versions of python, for some implementations of python, shouldn't you just assume all dictionaries are just unordered?
RE: Dictionary using variables as a keys - buran - Oct-10-2017
list1 = ['A4', 'A9', 'A2'] # keys
list2 = [27.8, 7.1, 68.04] # values
d = {k:v for k,v in zip(list1, list2) if v==min(list2)}
print dOutput:{'A9': 7.1}