Reduce

Reduce is a functionality that is introduced in Python that will take 2 elements at a time from either list or tuple and the result of that operation is again taken with next element in the list till we arrive at a solid answer and the list or tuple traversing is complete.

Let’s understand this better with an example:

Line 2: We have imported reduce function from functools module.

Line 4: A list named reduce_me is created with 5 elements in it.

Line 5: Reduce function is called for first and the second element, the operation mentioned is multiplication (first*second) and the list i.e., reduce_me is passed to reduce function.

Line 6: The result of reduce operation is printed.

Output:

Let’s run the above code and see the output.

Let’s see how the result is arrived.

We have a list named reduce_me with elements 1,2,3,4,1. This list is passed to lambda reduce function which will perform multiplication of first and second number in the list.

First number in our list is 1 and second number is 2.

Multiplication of two numbers (1 and 2) is 2. Now, we have to use 2 (the result of multiplication of two numbers) and multiply with the next number i.e., 3. Now the result of multiplying 2 and 3 is 6.

Now, we have to use 6 and multiply with the next number i.e., 4. Now the result of multiplying 6 and 4 is 24. Now, we have to use 24 and multiply with the next number i.e., 1. Now the result of multiplying 24 and 1 is 24.

As all the values in the lists are traversed, reduce operation will stop here and the result is 24.

Reduce is very helpful for many business requirements.