Fold (higher-order function)
Okay kiddo, imagine you have a big pile of toys on the floor, and you want to put them back in their respective boxes - cars in the car box, dolls in the doll box, and so on. But there are so many toys that it will take you a lot of time to do it manually.
Now, imagine if you had a robot friend that could help you with this task. You tell the robot: "Hey, take one toy at a time and put it in the correct box."
This is similar to a fold function, which is a computer program that takes a bunch of things and puts them in the right place. It helps you to process a big list of items efficiently.
Let's say you have a list of numbers: [1, 2, 3, 4, 5]. A fold function takes this list and summarizes all the values in the list into one single value.
For example, you could tell the computer "Hey fold function, add all the items in this list together." The fold function would then start with 0, take the first number in the list (1), add it to 0, and return 1. Then it would add 2 to 1, returning 3. It would keep adding the next items in the list until all items were accounted for, returning a final value of 15.
This is very handy as you don't have to manually add up all the numbers in the list by yourself. You can use this fold function for other operations as well, such as finding the maximum value, concatenating strings or counting items in a list.
So, fold function is like your robot friend that helps you to process a big pile of toys or a big list of items by organizing them in a specific way according to your instructions.
Now, imagine if you had a robot friend that could help you with this task. You tell the robot: "Hey, take one toy at a time and put it in the correct box."
This is similar to a fold function, which is a computer program that takes a bunch of things and puts them in the right place. It helps you to process a big list of items efficiently.
Let's say you have a list of numbers: [1, 2, 3, 4, 5]. A fold function takes this list and summarizes all the values in the list into one single value.
For example, you could tell the computer "Hey fold function, add all the items in this list together." The fold function would then start with 0, take the first number in the list (1), add it to 0, and return 1. Then it would add 2 to 1, returning 3. It would keep adding the next items in the list until all items were accounted for, returning a final value of 15.
This is very handy as you don't have to manually add up all the numbers in the list by yourself. You can use this fold function for other operations as well, such as finding the maximum value, concatenating strings or counting items in a list.
So, fold function is like your robot friend that helps you to process a big pile of toys or a big list of items by organizing them in a specific way according to your instructions.
Related topics others have asked about: