Python dict get any value

Accessing any element in a dictionary in Python

If mydict is not empty, I will access any element as follows:

#1st floor

If you only need to access one element (since dictionaries do not guarantee sorting, they are the first occasional element), you only need to Python 2 Do this:

my_dict.keys()[0] -> key of "first" element my_dict.values()[0] -> value of "first" element my_dict.items()[0] -> (key, value) tuple of "first" element

Note (to my knowledge) that Python does not guarantee that two consecutive calls to either of these methods will return a list in the same order.This functionality is not supported in Python 3.

list(my_dict.keys())[0] -> key of "first" element list(my_dict.values())[0] -> value of "first" element list(my_dict.items())[0] -> (key, value) tuple of "first" element

#2nd floor

Returns a value of type dict_keys(), in which case we get an error when we get the first member of the dict’s key:

dict.keys()[0] TypeError: 'dict_keys' object does not support indexing

Finally, I converted dict.keys() to list @ 1st and got the first member by splicing the list:

#3rd floor

import six six.next(six.itervalues(d))

#4th floor

On Python 3, nondestructive and iterative:

On Python 2, nondestructive and iterative:

If you want it to work in both Python 2 and 3, you can use the following six packages:

six.next(six.itervalues(mydict))

Although it’s still mysterious at this point, I still like your code better.

If you want to delete any items, do the following:

Note that «first» is not an appropriate term here.This is an «any» item because dict is not of an ordered type.

#5th floor

As others have mentioned, there is no First Item because dictionaries have no guaranteed order (they are implemented as hash tables).For example, if you want a value corresponding to the minimum key, the Dict [min (thedict)] will do this.If you care about the order in which keys are inserted, that is, first refers to the earliest insertion, in Python 3.1 you can use collections.OrderedDict For older versions of Python, download, install, and use ordered dict reverse migration (version 2.4 and later), which you can use in here Find it.

Python 3.7 Now? Dictionaries are sorted in insertion order.

#6th floor

Ignoring the issue of dictionary sorting might be better:

In this way, we avoid item lookups and generate lists of keys that we don’t use.

Python3

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Get value from dictionary by key with get() in Python

This article describes how to get the value from a dictionary ( dict type object) by the key in Python.

If you want to extract keys by their values, see the following article.

Get value from dictionary with dictPython dict get any value ( KeyError for non-existent keys)

In Python, you can get the value from a dictionary by specifying the key like dictPython dict get any value .

d = 'key1': 'val1', 'key2': 'val2', 'key3': 'val3'> print(d['key1']) # val1 

In this case, KeyError is raised if the key does not exist.

# print(d['key4']) # KeyError: 'key4' 

Specifying a non-existent key is not a problem if you want to add a new element.

For more information about adding items to the dictionary, see the following article.

Use in to check if the key exists in the dictionary.

Use dict.get() to get the default value for non-existent keys

You can use the get() method of the dictionary ( dict ) to get any default value without an error if the key does not exist.

Specify the key as the first argument. If the key exists, the corresponding value is returned; otherwise, None is returned.

d = 'key1': 'val1', 'key2': 'val2', 'key3': 'val3'> print(d.get('key1')) # val1 print(d.get('key4')) # None 

You can specify the default value to be returned when the key does not exist in the second argument.

print(d.get('key4', 'NO KEY')) # NO KEY print(d.get('key4', 100)) # 100 

The original dictionary remains unchanged.

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Python — Access Dictionary Items

You can access the items of a dictionary by referring to its key name, inside square brackets:

Example

Get the value of the «model» key:

There is also a method called get() that will give you the same result:

Example

Get the value of the «model» key:

Get Keys

The keys() method will return a list of all the keys in the dictionary.

Example

The list of the keys is a view of the dictionary, meaning that any changes done to the dictionary will be reflected in the keys list.

Example

Add a new item to the original dictionary, and see that the keys list gets updated as well:

Get Values

The values() method will return a list of all the values in the dictionary.

Example

The list of the values is a view of the dictionary, meaning that any changes done to the dictionary will be reflected in the values list.

Example

Make a change in the original dictionary, and see that the values list gets updated as well:

Example

Add a new item to the original dictionary, and see that the values list gets updated as well:

Get Items

The items() method will return each item in a dictionary, as tuples in a list.

Example

Get a list of the key:value pairs

The returned list is a view of the items of the dictionary, meaning that any changes done to the dictionary will be reflected in the items list.

Example

Make a change in the original dictionary, and see that the items list gets updated as well:

Example

Add a new item to the original dictionary, and see that the items list gets updated as well:

Check if Key Exists

To determine if a specified key is present in a dictionary use the in keyword:

Example

Check if «model» is present in the dictionary:

thisdict = <
«brand»: «Ford»,
«model»: «Mustang»,
«year»: 1964
>
if «model» in thisdict:
print(«Yes, ‘model’ is one of the keys in the thisdict dictionary»)

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Getting Values from a Dictionary in Python

To access all values in a dictionary in Python, call the values() method.

Or if you want to get a single value, use the square bracket [] access operator:

In case you’re unsure whether the value exists, it makes more sense to use the dict.get() method to access the values. This prevents the program from crashing if the value doesn’t exist.

This is the quick answer. But let’s take a more detailed look at accessing dictionary values in Python.

How to Get All Dictionary Values in Python

If you want to get all the values of a dictionary, use the values() method.

player_data = values = player_data.values()

This returns a dict_keys object. But you can convert it to a list using the list() function:

Now, this list contains all the values from the dictionary (the player numbers):

How to Get a Dictionary Value in Python

There are two ways to access a single value of a dictionary:

1. Get a Dictionary Value with Square Brackets

To get a single value from a dictionary, use the square brackets approach.

To do this, place the key whose value you are looking for inside square brackets after the dictionary:

player_data = ronaldo_number = player_data["Ronaldo"] print(ronaldo_number)

The problem with this approach is if there is no such key-value pair in the dictionary, an error is thrown and your program crashes.

For instance, let’s try to get a number of a player that does not exist:

player_data = rivaldo_number = player_data.get("Rivaldo") print(rivaldo_number)

To overcome this issue, use the get() method to get a value from a dictionary instead.

2. Python Dictionary get() Method

In addition to using square brackets to access dictionary values in Python, you can use the get() method.

To do this, enter the key whose value you are searching for inside the get() method.

player_data = ronaldo_number = player_data.get("Ronaldo") print(ronaldo_number)

Now if you try to access a non-existent value from the dictionary, you get a None back. This is better as your program does not crash even the value you are looking for is not there:

player_data = rivaldo_number = player_data.get("Rivaldo") print(rivaldo_number)

Conclusion

To access a dictionary value in Python you have three options:

1. Use the dictionary.values() method to get all the values
2. Use the square brackets [] to get a single value (unsafely).
3. Use the dictionary.get() method to safely get a single value from a dictionary.

Using get() is safe because it returns None if the value is not found. Using square brackets crashes your program if the value is not found.

Thanks for reading. I hope you found the values you were looking for. Happy coding!

Further Reading

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