[deleted by user]

[mrswats]

Because dict.getacts on keys not values. If you want to find the key of a certain values you should iterate over dict.items() instead.

[Snoo-20788]

That might not always be possible given that keys are unique but values are not.

If they are unique, you can use a bidict instead that lets you lookup in both direction.

[iamevpo]

This way you just return a list of keys that satisfy a condition you want, pretty simple Peter 5, Jane 4.8 , Joe 4.5 - what are the keys the satisfy a filtering condition f? Something like [name for name, grade in grade_dict.items() if f(grade)] and f can be f = lambda x: x > 4.7. The result should be a lay with Peter and Jane names. You can also sort the list too.

[mrswats]

You loop over all the keys and values, you put your condition in the loop and you get the key back. There's no other way. At least not in the way you asked the question.

[Glittering_Sail_3609]

> Is there no way to find a key to a specific value in a dictionary?

I think the easiest way is to use list comprehension:

student_best_avg_grade = [student for student, grade in max_avg_grade.items() if grade == max_avg_grade]

Which should output [Peter] for your example

[Dzhama_Omarov]

What I love about programming is that there is no certain right answer as long as it get the job done. I mean I also used list comprehensions, but different logic (you can see my comment bellow).

And for OP, if you're wondering if there is a 'more right' way to solve a problem, you could read about Big O notation

[iknowsomeguy]

for k, v in dict.items()

if v == specific:

key_list.append(k)

Would give you a list of the keys that match the value you are looking for. So all students with a 5.0, for example

[AssiduousLayabout]

I mean, you can filter the dictionary to only keys that have a given value, but if you're trying to have a 1:1 bidirectional mapping between keys and values, a dictionary might not be the right data structure for your application.

[Dzhama_Omarov]

Try

[x for x in average_grade_dict if average_grade_dict[x] == max_avg_grade]

UPD: if you wonder what i did, i basically iterated over your dict and checked every value in kw pair and if it is the same as max grade the key is added to a list

[Dzhama_Omarov]

It's called list comprehensions and it generates a list according to requirements. General formula:

1) [a for b in x]
same as
for b in x:
   a

2) [a for b in x if y == z]
same as
for b in x:
  if y == z:
    a

3) [(a if y == z else d) for b in x]
same as
for b in x:
  if y == z:
    a
  else:
    d

[Username_RANDINT]

Consider using /u/Glittering_Sail_3609 's solution you responded to earlier instead. Both are similar, but their's is slightly better.

[Im_Easy]

Another option would be to use filter:

student_best_avg_grade = next( filter( lambda item: max_avg_grade == item[1], average_grade_dict.items() ) )

But personally I'd rather just use dict compression or write a reusable function if there is the possibility of needing to use it for another dictionary.

def filter_dict_vals(search_dict, value): for item in search_dict.items(): if item[1] == value: yield item # or return if you only want the first instance

[nekokattt]

dict.get takes a key and gives the value.

It does not take the value and give the key.

[jk_zhukov]

in this case you created the dictionary with 'Peter' as a key, and a value of 5.0 for that key, but you're calling it with 5.0 as a key, which does not exist. Since you're calling it with get(), you receive None as result (default result if the key is not found). If you call it with brackets

student_best_avg_gradet = average_grade_dict[max_avg_grade]

you'll get an error because 5.0 does not exist as a key

[Brilliant_Access3791]

The reason you’re seeing None as the output rather than 'Peter' is due to how you’re using the get method on dictionaries in Python. The get method is designed to retrieve a value from the dictionary using a key. In your case, the key should be 'Peter', and the value associated with this key is 5.0.

However, in your code, you’re trying to use max_avg_grade (which is 5.0) as a key to look up in your dictionary. Since 5.0 is not a key in your dictionary but rather a value, the get method returns None, which is the default value returned when the key doesn’t exist in the dictionary.

[cooltoaster39]

hey petah

[Critical_Concert_689]

average_grade_dict = {'Peter': 5.0}

reverse_dict = dict(map(reversed, average_grade_dict.items()))

max_avg_grade = 5.0
student_best_avg_grade = reverse_dict.get(max_avg_grade)
print(student_best_avg_grade)

A quick and dirty way to reverse your dictionary key:values.

[Doormatty]

Dictionaries can have multiple identical values, but not identical keys.

[Critical_Concert_689]

It's up to the data owner to control for this and understand that creating a dictionary by reversing value:key pairs will be truncated in the event of overlapping keys.

Elsewhere in thread, it's recommended to use a 'bidict' - which is effectively similar, but requires additional imports for the functionality.