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JavaScript Object-Oriented JavaScript (2015) Introduction to Methods Adding a Method to an Object

Craig Curtis
Craig Curtis
19,985 Points
Posted by Craig Curtis
Craig Curtis
19,985 Points

Why did Mr. Chalkley use Math.floor(Math.random() * sides) + 1 instead of Math.ceil(Math.random * sides) ??

Shouldn't we write less code? Or is he (Mr. Chalkley) just showing the mechanics of Math.random() as being a float between 0 and 1?

2 Answers

Seth Kroger
Seth Kroger
56,403 Points
Seth Kroger
Seth Kroger
56,403 Points

Math.random() can return 0 and Math.ceil(0) is 0. So the latter code will return a random number from 0 to sides instead of from 1 to sides like the former.

David Zalk
David Zalk
2,729 Points
David Zalk
David Zalk
2,729 Points

because math floor rounds down and you add the 1 to bring it up to the next integer because you rounded down.