Python – Filter dictionaries with ordered values

When filtering dictionaries to find those with values in ascending order, we can use the sorted() method along with list comprehension to compare the original values with their sorted version.

Syntax

[dict for dict in list_of_dicts if sorted(dict.values()) == list(dict.values())]

Example

Below is a demonstration of filtering dictionaries with ordered values ?

my_list = [{'python': 2, 'is': 8, 'fun': 10},
           {'python': 1, 'for': 10, 'coding': 9},
           {'cool': 3, 'python': 4}]

print("The list is:")
print(my_list)

my_result = [index for index in my_list if sorted(
    list(index.values())) == list(index.values())]

print("The resultant dictionary is:")
print(my_result)

The output of the above code is ?

The list is:
[{'python': 2, 'is': 8, 'fun': 10}, {'python': 1, 'for': 10, 'coding': 9}, {'cool': 3, 'python': 4}]
The resultant dictionary is:
[{'python': 1, 'for': 10, 'coding': 9}]

How It Works

The solution works by extracting values from each dictionary and comparing them with their sorted version:

• Extract dictionary values using dict.values()

• Sort the values using sorted()

• Compare sorted values with original values

• Keep only dictionaries where values are already in ascending order

Alternative Approach Using Lambda

You can also use the filter() function with a lambda expression ?

my_list = [{'python': 2, 'is': 8, 'fun': 10},
           {'python': 1, 'for': 10, 'coding': 9},
           {'cool': 3, 'python': 4}]

my_result = list(filter(lambda d: sorted(d.values()) == list(d.values()), my_list))

print("Filtered dictionaries:")
print(my_result)

Filtered dictionaries:
[{'python': 1, 'for': 10, 'coding': 9}]

Conclusion

Use list comprehension with sorted() to filter dictionaries based on ascending value order. This approach efficiently compares original values with their sorted counterparts to identify properly ordered dictionaries.