Create an empty dictionary python

How to create an empty Python dictionary

In this Python tutorial, we will discuss How to create an empty Python dictionary Here we will also cover the below examples:

• How to create an empty dictionary in Python with keys
• How to create empty nested dictionary Python
• How to check if Python dictionary is empty

How to create an empty Python dictionary

• In Python to create an empty dictionary, we can assign no elements in curly brackets <>.
• We can also create an empty dictionary by using the dict() method it is a built-in function in Python and takes no arguments.

Let’s take an example and check how to create an empty dictionary in Python

my_new_dict = <> print("Created empty dictionary:",my_new_dict) print(type(my_new_dict)) 

So, with this above code, we create an empty dictionary that is ‘my_new_dict’ and it is equal to curly brackets<>. Now if you want to see an empty dictionary in output then you have to use a print statement. It will display an empty dictionary and type of dictionary.

Here is the Output of the following given code.

Another example to create an empty dictionary by using dict() built-in function

In Python, an empty dictionary means that it does not contain key-value pair elements. In this example to create an empty dictionary, we can use a dict constructor and this method takes no arguments. If no argument is passed then it creates an empty dictionary.

Source Code:

emp_num = dict() print("Empty dictionary:",emp_num) print(type(emp_num))

This is how to create an empty dictionary in Python.

How to create an empty dictionary in Python with keys

In Python to create an empty dictionary with keys, we can use the combination of zip() and len() method. This method will initialize a dictionary of keys and returns no values in the dictionary.

Source Code:

new_key_lis = [18,23,45] b= dict([(23,18)]) c = dict(zip(new_key_lis, [None]*len(new_key_lis))) print(c)

Here is the Implementation of the following given Code

How to create empty nested dictionary

• Here we can see how to create an empty nested dictionary in Python.
• In this example, we use the concept of the dict() method to create an empty nested dictionary. The dict() method is a built-in function in Python and it takes no arguments.

new_dict = < '': < >, '': < >> print("Empty Nested dictionary:",new_dict)

Here is the execution of the following given code

How to check if Python dictionary is empty

• To check if the Python dictionary is empty or not we can use the if condition. It will check the condition if the dictionary contains elements or not. The if condition will return true if the dictionary is empty otherwise it will return false.
• There are various method to solve this task
  • By using if condition
  • By using not operator
  • By using bool(dict) method
  • By using len() method

  By using if condition

  In Python the, ‘if’ condition verifies if the dictionary contains elements or not. So in the below code, we will check the condition.

  Source Code:

  my_dictionary = new_dictionary = <> if my_dictionary: print("my_dictionary is not empty") else: print("my_dictionary is empty") if new_dictionary: print("new_dictionary is not empty") else: print("new_dictionary is empty")

  In the above code first, we will initialize two dictionaries. The first dictionary contains key-value pair and the second dictionary creates an empty dict. Now use the if condition and check which dictionary is empty. To do this we use the if-else condition and if the dictionary contains an element then it will display the dictionary is not empty.

  Here is the Screenshot of the following given code

  

  By using not operator

  In Python to applying the not operator in a dictionary, we will first initialize an empty dictionary and use the ‘not’ operator to check if the dictionary is empty.

  Let’s take an example and check if the Python dictionary is empty or not

  my_emp_dict = <> new_out = not my_emp_dict print("Dictionary is epty or not?:",new_out)

  

  By using bool() dict method

  To check if the dictionary is not empty then it will return true by using the bool() method. This method is used to return a boolean value that means it will display in the output True or False and it takes only one argument.

  Source Code:

  my_new_dict = <> emp_val = bool(my_new_dict) print(emp_val)

  Here is the execution of the following given code

  

  By using len() method

  An alternative way to check if the dictionary is empty or not in Python is by using the len() method.

  Source Code:

  you_dictionary = <> new_emp_dict = len(you_dictionary) if new_emp_dict == 0: print ("Empty dictionary") else: print ("Dictionary is not empty") 

  In the above code first, we will initialize an empty dictionary ‘you_dictionary’. After that, we use the len() function to calculate the length of the dictionary and contain it in the variable ‘new_emp_dict’ and use the if statement condition to check if the dictionary is empty or not.

  Here is the implementation of the following given code

  

  You may also like reading the following tutorials.

  In this Python tutorial, we have discussed How to create an empty Python dictionary Here we have also covered the following topics:

  • How to create an empty dictionary in Python with keys
  • How to create empty nested dictionary Python
  • How to check if Python dictionary is empty

  I am Bijay Kumar, a Microsoft MVP in SharePoint. Apart from SharePoint, I started working on Python, Machine learning, and artificial intelligence for the last 5 years. During this time I got expertise in various Python libraries also like Tkinter, Pandas, NumPy, Turtle, Django, Matplotlib, Tensorflow, Scipy, Scikit-Learn, etc… for various clients in the United States, Canada, the United Kingdom, Australia, New Zealand, etc. Check out my profile.

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  Create Empty Dictionary in Python (5 Easy Ways)

  

  Dealing with data structure is the most fundamental thing while working with any programming language. Dictionary is one such primary data structure frequently used by every programmer while coding in python. However, there are times when you need to check whether the dictionary is empty or not. To help you with the same, we will discuss some of the common methods to check python empty dictionary along with examples and output. But before that, let’s have flashback to python dictionary below. So, let’s get started!

  What is Python Dictionary?

  Dictionary in Python is an unordered collection of data values, used to store data values like a map, which, unlike other Data Types that hold only a single value as an element. Dictionary holds the key: value pair to make it more optimized. Each key-value pair in a Dictionary is separated by a colon(:) whereas each key is separated by a ‘comma’. A Dictionary in python is declared by enclosing a comma-separated list of key-value pairs using curly braces <>.

  For example:

  sample_dict = < "fruit": "mango", "vegetable": "potato", "flower": "rose" > print(sample_dict)

  How to Create an Empty Dictionary in Python?

  Below are three common methods by which you can create an empty dictionary in python:

  1) By declaring empty dictionary

  In Python, we can create an empty dictionary by putting no elements inside curly brackets. Check out the below example to better understand this method.

  For example:

  myDictioanry = <> print("Created empty dictionary:",myDictioanry) print(type(myDictioanry))

  2) Using dict() method

  Python empty dictionary means that it does not contain any key-value pair elements. To create an empty dictionary in this example, we can use a dict(), which takes no arguments. If no arguments are provided, an empty dictionary is created.

  For example:

  myDictionary = dict() print("Empty dictionary:",myDictionary) print(type(myDictionary))

  3) Using keys

  In Python, we can use the zip() and len() methods to create an empty dictionary with keys. This method creates a dictionary of keys but returns no values from the dictionary.

  For examples:

  keyList = [8,2,5] mailcap= dict([(8,5)]) n = dict(zip(keyList, [None]*len(keyList))) print(n)

  4) Create an empty nested dictionary

  In this method, we use the dict() method concept to create an empty nested dictionary. The dict() method is a Python built-in function that accepts no arguments.

  For example:

  myDictionary = < '': < >, '': < >> print("Empty Nested dictionary:",myDictionary)

  5) Check if the python dictionary is empty

  The “if condition” can be used to determine whether or not the Python dictionary is empty. It will determine whether or not the dictionary contains elements. If the dictionary is empty, the “if condition” returns true; otherwise, it returns false.

  For example:

  myDictionary = 1:"b",9:"c",2:"p"> newDictionary = <> if myDictionary: print("myDictionary is not empty") else: print("myDictionary is empty") if newDictionary: print("newDictionary is not empty") else: print("newDictionary is empty")

  myDictionary is not empty newDictionary is empty

  Also, you can use the “not operator”, “bool(dict)” or “len()” method instead of “if condition” to check the python empty dictionary.

  Conclusion

  Dictionary plays an important role while coding in python. In this article, we understood how you can check whether the dictionary you are working with is empty or not. We learned five explicit methods to check the python empty dictionary with various examples and output. We recommend you to use all these methods efficiently to make your coding easy and efficient.

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  How to Create an Empty Dictionary in Python

  

  In this article, we show how to create an empty dictionary in Python.

  A dictionary in Python is really an associative array or hash table that is composed of key-value pairs. So if you have a dictionary called itemprices, one key may be «T-shirt» with a value of 24.95, another key may be «Brief» with a value of 14.95, and another key may be «Pants» with a value of 34.95.

  Though most times, you would probably create a dictionary with elements in them, other times you may want to create an empty dictionary.

  An empty dictionary is a dictionary that contains no items (no key:value pairs).

  You may create an empty dictionary if you want a user to populate the dictionary.

  For example, you create an empty dictionary and then receive input from a user and then populate the dictionary based on the user input.

  So now we’ll go over how to create an empty dictionary in Python.

  How to Create an Empty Dictionary in Python

  To create an empty dictionary, the dictionary should be set to <>.

  This is shown in the code below.

  So, with this code above, we create a dictionary called items which is set equal to <>. So this dictionary named items is empty.

  Another way of creating an empty dictionary is by setting the dictionary equal to dict().

  This is shown in the code below.

  So, this dictionary named items is an empty dictionary.

  And this is all that is required to create an empty dictionary in Python.

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