Python dict get one value

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 one value ( KeyError for non-existent keys)

In Python, you can get the value from a dictionary by specifying the key like dictPython dict get one 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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Get First Key and Value in Dictionary with Python

In Python, there are a few different ways we can get the first key/value pair of a dictionary. The easiest way is to use the items() function, convert it to a list, and access the first element.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_item = list(dictionary.items())[0] print("The first item of the dictionary has key: " + first_item[0] + " and value: " + first_item[1]) #Output: The first item of the dictionary has key: key1 and value: This

Another way to get the first key and value in a dictionary is to convert it to a list and access the first element. This will get the first key, and then you can get the first value by accessing that key in the

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_key = list(dictionary)[0] print("The first key of the dictionary is: " + first_key) #Output: The first key of the dictionary is: key1

If you only care about getting the first value of a dictionary, you can use the dictionary values() function.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_value = list(dictionary.values())[0] print("The first value of the dictionary is: " + first_value) #Output: The first value of the dictionary is: This

In Python, dictionaries are a collection of key/value pairs separated by commas. When working with dictionaries, it can be useful to be able to easily access certain elements.

We can easily get the first item from a dictionary and get the first key and first value.

The easiest way to get the first item from a dictionary is with the items() function. The items() function returns a dict_items object, but we can convert it to a list to easily and then access the first element like we would get the first item in a list.

Below is an example of how you can use the dictionary items() function to get the first item of a dictionary.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_item = list(dictionary.items())[0] print(first_item) print("The first item of the dictionary has key: " + first_item[0] + " and value: " + first_item[1]) #Output: ('key1','This') The first item of the dictionary has key: key1 and value: This

Get First Key in Dictionary Using Python

The example above is great for getting the first item in a dictionary. If you only care about getting the first key, there are a few ways you can get the first key of a dictionary.

You can use the Python dictionary keys() function, convert it to a list, and access the first element, or just convert the dictionary to a list and then access the first element.

Below shows two different ways to get the first key from a dictionary in Python.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_key = list(dictionary)[0] print("The first key of the dictionary is: " + first_key) first_key = list(dictionary.keys())[0] print("The first key of the dictionary is: " + first_key) #Output: The first key of the dictionary is: key1 The first key of the dictionary is: key1

Get First Value in Dictionary Using Python

If you only care about getting the first value, there are a few ways you can get the first value of a dictionary.

To get the first value in a dictionary, you can use the Python dictionary values() function, convert it to a list, and access the first element.

Below shows two different ways to get the first value from a dictionary in Python.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >first_value = list(dictionary.values())[0] print("The first value of the dictionary is: " + first_value) #Output: The first value of the dictionary is: This

Get the First n Items in Dictionary Using Python

We can use the items() function to get the first n items in a dictionary using Python. Since we convert the dict_items object to a list, we can use slicing just like with lists to get the first n key/value pairs in a dictionary.

Below is an example of how you can use Python to get the first 3 items in a dictionary.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >dict_items_list = list(dictionary.items())[0:3] for x in dict_items_list: print(x) #Output: ('key1', 'This') ('key2', 'is') ('key3', 'a')

Get the Last Item in Dictionary Using Python

Finally, if you want to get the last item in a dictionary, or get the last key and last value, you can use a very similar method as described above.

Now, instead of getting the first element, we get the last item from the list.

Below is an example in Python of how to get the last key and last value in a dictionary.

dictionary = < "key1":"This", "key2":"is", "key3":"a", "key4":"dictionary." >last_item = list(dictionary.items())[-1] print("The first item of the dictionary has key: " + last_item[0] + " and value: " + last_item[1]) #Output: The first item of the dictionary has key: key4 and value: dictionary.

Hopefully this article has been useful for you to understand how to get the first item from a dictionary in Python.

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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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