How to Create a String of N Characters in Python

In this Python tutorial, you will learn How Python create a string with N characters in different ways with multiple practical examples.

Suppose we have a collection of characters and must create a string by merging the characters according to our range. We can use these approaches to get the required output in this situation.

4 Different Examples of Creating a String with N Characters in Python

Let me explain the scenario more clearly so you can use these techniques correctly.

Here’s a collection of characters,

characters = ['C', 'A', 'L', 'I', 'F', 'O', 'R', 'N', 'I', 'A']

Now, I need to merge some characters from the collection and create a new string of those merged characters like this,

CALIFOR

So, we’ve found multiple solutions to get this output type by merging the strings in Python.

Let’s understand all approaches one by one with practical examples.

Python Create a String with N Characters Using a For-Loop

First, we will use a for-loop to target every character individually and merge it into the string based on the given N range.

Also, we will include exception handling (try and except) because the user may give a range larger than the length of the collection of characters, which will give an error like this: “IndexError: list index out of range.” To handle the IndexError, we are using the try and except block.

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Here’s an example of How Python create a string with n characters using a for-loop

characters = ['C', 'A', 'L', 'I', 'F', 'O', 'R', 'N', 'I', 'A']

user_input = int(input("How much characters you want to merge: "))
string = ''

try:  
    for i in range(user_input):
        string+=characters[i]
    print(string)
except IndexError:
    print("Please Enter a Valid Range")
Python create a string with n characters using a for-loop

In the above code, we have a list of characters and must merge some characters based on the user_input. So, we used a for loop “for i in range(user_input)” to iterate over every character and include it in the string variable “string+=characters[I]” until the range matches.

If the user inputs an invalid range, the code can handle the errors using a try-and-except block ‘except IndexError‘.

Create a string of N characters in Python using the while loop

Here, we use the same logic as in the previous example, but this time, we will use a while loop to create a string with N characters.

The while loop runs a particular code block multiple times and stops only when the condition becomes False.

Here’s an example of How Python create a string with n characters using a while loop

characters = ['N', 'E', 'W', ' ' , 'Y', 'O', 'R', 'K']

user_input = int(input("How much characters you want to merge: "))
string = ''
i = 0 

while i<user_input:
    string += characters[i]
    i+=1

print(string)
Create a string of N characters in Python using while loop

In the above code, we have a list of characters, and then we take the user input to get the range and initialize i = 0. Then, we use the same logic in the previous example. The difference is that in the while loop, you have to increase the value of i, like i+=1 manually.

How Python create a string with n characters using join() and List comprehension

We can also use the join() method and List comprehension in Python to create a string with n characters. We will use a one-liner for loop inside List comprehension, and then we will use the join() method to concatenate the characters one by one.

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Syntax according to our program.

" ".join(lis_of_characters[index] for index in range(length))
  • The syntax contains an empty string, which we use to concatenate using the join() method.
  • lis_of_characters[index] for index in range(length): Then, use a one-liner for loop to iterate over every collection element.

Here’s an example of How Python create a string with n characters using a join method and list comprehension.

# Using list comprehension

characters = ['L', 'O', 'N', 'D', 'O', 'N']

user_input = int(input("How much characters you want to merge: "))

try:
    string = ''.join(characters[i] for i in range(user_input))
    print(string)
except IndexError:
    print("Please Enter a Valid Range")
How Python create string with n characters using join() and list comprehension

In the above code, we are taking user input and then using a one-liner for loop inside list comprehension like this: “characters[i] for i in range(user_input)”, so it will target all the characters one by one, then it will be assigned to string as str with the help of join()
string = ”.join(characters[i] for i in range(user_input)) method.

Python create a string of length using chr() and for loop

Let’s try to create a string based on the length of another collection using the len() method. We will create a string of the sequence of alphabetical characters with the help of the chr() method in Python.

The chr() method converts the ASCII value to a character in Python, and the len() method returns the count of the collection’s existing elements.

# Python create string of length
characters = ['C', 'A', 'L', 'I', 'F', 'O', 'R', 'N', 'I', 'A']

string = ''
for i in range(0,len(characters)):
    string += chr(65+i)

print(string)
Python create string of length using chr() and for loop

In the above code, we have a collection, so based on its length, we are creating Uppercase Alphabets using the chr() method.

So we are giving (65+i), which means 65 is the Ascii value of “A.” We’ve given the range based on collection length so that it will iterate for a given length (character) times and increment by 1 in every iteration. This is how it will print the alphabet in sequence.

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Conclusion

In this Python article, you learned how to create a string with N characters using different approaches, such as using a for loop, while loop, or list comprehension, and some built-in methods, like len(), chr(), and join().

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