List of Numbers From 1 to N in Python

Manav Narula Jul-18, 2021 Mar-27, 2021 Python Python List

This tutorial will discuss how to create a list of numbers from 1 to some specified number.

Create a User-Defined Function to Create a List of Numbers From 1 to N

This method will take the required number from the user and iterate till that number using the `for` loop. In each iteration, we will increment the value and append the number to a list.

The following code will explain this.

``````def createList(n):
lst = []
for i in range(n+1):
lst.append(i)
return(lst)

print(createList(10))
``````

Output:

``````[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
``````

Use the `range()` Function to Create a List of Numbers From 1 to N

The `range()` function is very commonly used in Python. It returns a sequence between two numbers given in the function arguments. The starting number is 0 by default if not specified. It also has a parameter called `step`, which can specify the incrementation and is one by default.

In the code below, we will generate a list of numbers using this function.

``````lst = list(range(1,10+1))
print(lst)
``````

Output:

``````[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
``````

Note the use of the `list()` function. It ensures that the final result is in a list form. Also, notice the use of `+1`, which ensures that the final number is also included in the list.

We can also use the list comprehension method with the `range()` function. List Comprehension is a simple, concise way of creating a list in Python.

This method is shown below:

``````lst = [i for i in range(1,10+1)]
print(lst)
``````

Output:

``````[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
``````

Use the `numpy.arange()` to Create a List of Numbers From 1 to N

The `NumPy` module has many useful methods to create and modify arrays. The `arange()` function from this module is similar to the `range()` function discussed earlier. The final output is a numpy array.

We will implement this function in the code below.

``````import numpy as np
lst = list(np.arange(1,10+1))
print(lst)
``````

Output:

``````[1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
``````

We also use the `list()` function to convert the final output to a list form.

Author: Manav Narula

Manav is a IT Professional who has a lot of experience as a core developer in many live projects. He is an avid learner who enjoys learning new things and sharing his findings whenever possible.