Python last element dictionary

Get last element of dictionary python

dict.keys() returns a list of your dictionary’s keys. Once you got the list, the -1 index allows you getting the last element of a list.,We need to convert the dictionary keys to a list object, and use an index of -1 to print out the last element.,#this will return last element of dictionary dictObj[len(dictObj.keys()) — 1],Since a dictionary is unordered*, it’s doesn’t make sense to get the last key of your dictionary.

It seems like you want to do that:

Perhaps you want to sort them before. It would look like that:

Answer by Dalary Rowland

Answer by Dominik Brown

We need to have two points in mind:,Getting the first or last element of a dictionary Python is not intuitive operation but it is easy.,Second it’s difficult to point the first and last element of a Dictionary,First value or element of a dictionary in Python can be extracted by code like:

If the order of the elements is not important for you then you can get several N elements of a dictionary by next code example:

mydict = for x in list(mydict)[0:3]: print (x) 

First value or element of a dictionary in Python can be extracted by code like:

mydict = for x in list(mydict)[0:3]: print (mydict[x]) 

When order of the elements is not important all items can be get and extracted by:

mydict = for i in mydict.items(): print(i) 

It’s possible to use the list method to extract the first 3 keys — list(mydict)[0:3] . So extracting first 3 elements from dictionary is done by extracting first keys and getting their values:

mydict = for x in list(mydict)[0:3]: print ("key <>, value <> ".format(x, mydict[x])) 

key 1, value a key 2, value b key 3, value c 

This will help you to get the elements of a Python dict in different order. For example, the next code is getting the last N items from a dictionary in Python.

mydict = for x in list(reversed(list(mydict)))[0:3]: print (x) 

Let’s do a quick experiment in Python 3.7. First let’s create a simple dictionary:

for i in mydict.items(): print(i) 

for i in mydict.items(): print(i) 

Can you guess the output of the previous command? If you think that element (0, ‘z’) will be the last one. Congratulations! You are a good programmer!

Now let’s delete element with key 3 and value c of the same dictionary by:

Is it going to be in the same place or at the end?

Answer by Madelynn Whitehead

Example 1: get last element of dictionary python

Example 2: python get the last in dictionary

# import the right class from collections import OrderedDict # create and fill the dictionary d = OrderedDict() d['first'] = 1 d['second'] = 2 d['third'] = 3 # retrieve key/value pairs els = list(d.items()) # explicitly convert to a list, in case it's Python 3.x # get first inserted element els[0] => ('first', 1) # get last inserted element els[-1] => ('third', 3)

Answer by Briana Buckley

I have a long dictionary and I’ve to get the values of its first and last keys. I can use dict[dict.keys()[0]] and dict[dict.keys()[-1]] to get the first and last elements, but since the key:value pairs are outputted in a random form(as in the positioning of the key:value pairs is random), will the solution provided in this link always work?, python — How do I delete the first and last items in a list? , dictionary — How do I get the first three elements in Python ordereddict? ,Before posting, I have already gone through Access an arbitrary element in a dictionary in Python, butI’m uncertain about this.

Before posting, I have already gone through Access an arbitrary element in a dictionary in Python, butI’m uncertain about this.

I have a long dictionary and I’ve to get the values of its first and last keys. I can use dict[dict.keys()[0]] and dict[dict.keys()[-1]] to get the first and last elements, but since the key:value pairs are outputted in a random form(as in the positioning of the key:value pairs is random), will the solution provided in this link always work?

Before posting, I have already gone through Access an arbitrary element in a dictionary in Python, butI’m uncertain about this.

I have a long dictionary and I’ve to get the values of its first and last keys. I can use dict[dict.keys()[0]] and dict[dict.keys()[-1]] to get the first and last elements, but since the key:value pairs are outputted in a random form(as in the positioning of the key:value pairs is random), will the solution provided in this link always work?

Answer by Cody Wong

Reverse the elements of the list in place.,Return the number of times x appears in the list.,Remove all items from the list. Equivalent to del a[:].,which, in turn, is the same as:

>>> fruits = ['orange', 'apple', 'pear', 'banana', 'kiwi', 'apple', 'banana'] >>> fruits.count('apple') 2 >>> fruits.count('tangerine') 0 >>> fruits.index('banana') 3 >>> fruits.index('banana', 4) # Find next banana starting a position 4 6 >>> fruits.reverse() >>> fruits ['banana', 'apple', 'kiwi', 'banana', 'pear', 'apple', 'orange'] >>> fruits.append('grape') >>> fruits ['banana', 'apple', 'kiwi', 'banana', 'pear', 'apple', 'orange', 'grape'] >>> fruits.sort() >>> fruits ['apple', 'apple', 'banana', 'banana', 'grape', 'kiwi', 'orange', 'pear'] >>> fruits.pop() 'pear' 

Answer by Legacy Kemp

The combination of the above methods can be used to perform this particular task. In this, we just convert the entire dictionaries’ keys extracted by keys() into a list and just access the first key. Just one thing you have to keep in mind while using this i.e it’s complexity. It will first convert the whole dictionary to list by iterating over each item and then extract its first element. Using this method complexity would be O(n).,A Time Complexity Question,Python | Split string into list of characters,Python | Get the first key in dictionary

Answer by Leanna Boyer

Using list[-1] syntax and I am assuming that you have a non-empty list.,To get the last element of the list in Python, we have two ways.,How to Get Last Element of a List in Python,In this list, the “astral” element is the last item, and to access that element, write the following code.

data = ["infy", "tcs", "affle", "dixon", "astral"]

In this list, the “astral” element is the last item, and to access that element, write the following code.

data = ["infy", "tcs", "affle", "dixon", "astral"] last_element = data[-1] print(last_element)

Output

If the expected item does not exist, then it will throw an IndexError. This means that list[-1] will raise an exception if the list is empty because an empty list can’t have the last element.

data = [] last_element = data[-1] print(last_element)

Output

Traceback (most recent call last): File "/Users/krunal/Desktop/code/pyt/database/app.py", line 3, in last_element = data[-1] IndexError: list index out of range

The list.pop() in the Python method removes and returns the object at the given index (passed as an argument) from a list.

data = ["infy", "tcs", "affle", "dixon", "astral"] last_element = data.pop() print(last_element)

Output

Answer by Celine Fuller

In this example, you will learn to get the last element of this list.,To understand this example, you should have the knowledge of the following Python programming topics:,If you want to learn more, please go to Python list Negative Indexing.,If you want the first 1st element, you can use my_list[-5].

Using negative indexing

my_list = ['a', 'b', 'c', 'd', 'e'] # print the last element print(my_list[-1])

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Python last element dictionary

Last updated: Feb 20, 2023
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# Table of Contents

# Get the last Key or Value in a dictionary in Python

Use the list() class to get the last key in a dictionary, e.g. list(my_dict)[-1] .

The list class converts the dictionary to a list of keys where we can access the element at index -1 to get the last key.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_key = list(my_dict)[-1] print(last_key) # 👉️ country print(my_dict[last_key]) # 👉️ Belgium first_key = list(my_dict)[0] print(first_key) # 👉️ id 

If you only need the last value, use the dict.values() method instead.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_value = list(my_dict.values())[-1] print(last_value) # 👉️ Belgium print(list(my_dict.values())) # 👉️ [1, 'Bobby Hadz', 'Belgium'] 

We used the list() class to get the last key in a dictionary.

The list() class converts the dictionary to a list of keys.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > print(list(my_dict)) # 👉️ ['id', 'name', 'country'] 

The last step is to access the list item at index -1 .

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > print(list(my_dict)) # 👉️ ['id', 'name', 'country'] last_key = list(my_dict)[-1] print(last_key) # 👉️ country last_value = my_dict[last_key] print(last_value) # 👉️ Belgium 

As of Python 3.7, the standard dict class is guaranteed to preserve the order of keys.

Negative indices can be used to count backward, e.g. my_list[-1] returns the last item in the list and my_list[-2] returns the second-to-last item.

Python indexes are zero-based, so the first item in a list has an index of 0 , and the last item has an index of -1 or len(my_list) — 1 .

# Get the last Key or Value in a dictionary using dict.keys() and dict.values()

You can also use the dict.keys() method explicitly to get the last key in a dictionary.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_key = list(my_dict.keys())[-1] print(last_key) # 👉️ 'country' print(my_dict[last_key]) # 👉️ 'Belgium' 

If you only need the last value, use the dict.values() method instead.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_value = list(my_dict.values())[-1] print(last_value) # 👉️ Belgium 

The dict.keys method returns a new view of the dictionary’s keys.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > # 👇️ dict_keys(['id', 'name', 'country']) print(my_dict.keys()) # 👇️ ['id', 'name', 'country'] print(list(my_dict.keys())) 

The dict_keys object is not subscriptable, so we can’t access it at a specific index.

We can convert the object to a list to get around this.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_key = list(my_dict.keys())[-1] print(last_key) # 👉️ 'country' 

You don’t have to use the my_dict.keys() method in this scenario because you can just pass the dictionary to the list() class to get a list of its keys.

However, you’ll often see this approach being used to get the last key in a dictionary.

# Get the last Key or Value in a dictionary using reversed()

Alternatively, you can use the reversed() function:

1. Get an iterator of the dictionary’s keys and reverse it.
2. Use the next() function to get the first key from the reversed iterator.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_key = next(reversed(my_dict.keys()), None) print(last_key) # 👉️ country last_value = my_dict[last_key] print(last_value) # 👉️ Belgium 

If you only need the last value, use the dict.values() method.

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my_dict =  'id': 1, 'name': 'Bobby Hadz', 'country': 'Belgium' > last_value = next(reversed(my_dict.values()), None) print(last_value) # 👉️ Belgium 

The reversed function takes an iterator, reverses it and returns the result.

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result = list(reversed(range(1, 11))) print(result) # 👉️ [10, 9, 8, 7, 6, 5, 4, 3, 2, 1] 

The next() function returns the next item from the provided iterator.

The function can be passed a default value as the second argument.

If the iterator is exhausted or empty, the default value is returned.

We used None as the default value, so if the dictionary is empty, None is returned.

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my_dict = > last_key = next(reversed(my_dict.keys()), None) print(last_key) # 👉️ None if last_key is not None: print(my_dict[last_key]) 

If the iterator is exhausted or empty and no default value is provided, a StopIteration exception is raised.

# Using the OrderedDict class in Python versions older than 3.7

If you use a version older than Python 3.7, then the order of the keys in a dictionary is not preserved and you have to use an OrderedDict .

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from collections import OrderedDict my_dict = OrderedDict( [('id', 1), ('name', 'Bobby Hadz'), ('country', 'Belgium')] ) last_key = list(my_dict)[-1] print(last_key) # 👉️ 'country' 

The list() class can also be used to convert the keys of an OrderedDict to a list.

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from collections import OrderedDict my_dict = OrderedDict( [('id', 1), ('name', 'Bobby Hadz'), ('country', 'Belgium')] ) print(list(my_dict)) # 👉️ ['id', 'name', 'country'] 

The last step is to access the key at index -1 to get the last key.

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

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