How To Solve Valueerror In Python

I'm working on a image search engine application, I have the code in separate .py files and it's working fine. But I want to optimize it. When I use the function below, it's giving

Solution 1:

So, my guess is that this part:

zip(*sorted(zip(res_lst_srt['values'], res_lst_srt['keys'])))

is returning an empty list to any of the zips:

>>> foo, bar = []
Traceback (most recent calllast):
  File "<stdin>", line 1, in<module>
ValueError: need more than 0valuesto unpack

Now, if you want to populate res_lst_srt (as it seems I understood from your question), why don't you make it simpler?

>>>values=[1,2,3]>>>keys=['a', 'b', 'c']>>>my_dict = dict(zip(keys, values))>>>my_dict
{'a': 1, 'c': 3, 'b': 2}

(values here would be res_lst_srt['values'], keys would be res_lst_srt['keys'] and my_dict would be res_lst_srt. No? Shouldn't that work?

Solution 2:

Your issue can be found by looking at this simple case.

>>> a, b = tuple() # or you could write a, b = []

Traceback (most recent call last):
  File "<pyshell#319>", line 1, in <module>
    a, b = tuple()
ValueError: need more than 0 values to unpack
>>> 

The length of values on one side of the equals operator must match the other.

So its clear that the values returned by..

zip(*sorted(zip(res_lst_srt['values'], res_lst_srt['keys'])))

..end up returning an empty list/tuple. Which is causing you grief.