Python : Generators
Generators in Python are a powerful tool that allow us to create iterators in a simple and efficient way. In this tutorial, we'll go over the basics of generators and how to create them in Python.
What is a Generator in Python?
A generator is a type of iterable, like lists, tuples, and sets. However, unlike those types of iterables, a generator doesn't store all of its values in memory at once. Instead, it generates each value on-the-fly as we iterate over it.
This means that generators are great for working with large data sets, since we don't need to load everything into memory at once. Instead, we can generate values as needed, and then move on to the next one.
Creating a Generator in Python
To create a generator in Python, we use a special type of function called a generator function. A generator function is similar to a regular function, but instead of using the
return keyword to
return a value, we use the
Here's an example of a simple generator function:
def count_up_to(n): i = 1 while i <= n: yield i i += 1
In above example, we define a generator function called
count_up_to that takes a single argument, n. We then use a while loop to generate values from 1 up to n.
yield keyword is what makes this function a generator. Each time we hit the
yield statement, we return the current value of i, but we don't exit the function. Instead, we pause the function and wait for the next call to generate the next value.
Using a Generator
To use a generator, we simply call the generator function, and then iterate over the values it generates.
Here's an example of how to use the
count_up_to generator function:
for i in count_up_to(5): print(i)
Benefits of Using a Generator
There are several benefits to using generators in Python:
generators don't load all values into memory at once, which makes them ideal for working with large data sets.
generator functions are easy to write and understand, and they allow us to create complex iterables with very little code.
generators only generate values as needed, which means we can stop generating values at any point without wasting resources.