Best way to check a value in a dictionary of lists?

Question

So, I have a dictionary of lists like this:

dct = {'1': ['hello','goodbye'], '2': ['not here','definitely not here']}

What's the fastest way to check if "hello" is in one of my lists in my dictionary

+3

citizen2077 01 Apr 17 at 17:41

1 answer

L3viathan · Accepted Answer · 2017-04-01T17:54:06+0000

As Willem Van Onsem commented, the easiest way to achieve this is:

any('hello' in val for val in dct.values())

any

returns True if any of the values in the given iterable file are true.

dct.values()

returns an dict_values

iterable that gives all the values in the dictionary.

'hello' in val for val in dct.values()

is a generator expression that gives True

for each value dct

it is in 'hello'

.

If you want to know the keys that the string goes in, you can:

keys = [key for key, value in dct.items() if 'hello' in value]

In your case, it keys

will be ['1']

. If you do it anyway, you can just call that list in a boolean context, eg. if keys: ...

...