Ruby .ceil and .floor

Question

I'm new to Ruby and I'm trying to figure out how ceil and floor works as I get different answers when a fraction or a decimal number is used (similar value). Below is what I have tried:

puts 8/3.ceil == 2   #=> true puts 8/3.floor == 2  #=> true puts 2.67.ceil == 2  #=> false puts 2.67.floor == 2 #=> true 

From my understanding, ceil should return a number higher and floor is a number lower. Hope someone can enlighten me on this. Thank you! :)

Answer 1

Everything is returned correctly.

puts 8/3.ceil == 2 #=> true, because 8/3 returns an Integer, 2 puts 8/3.floor == 2 #=> true, because 8/3 returns an Integer, 2 puts 2.67.ceil == 2 #=> false, because 2.67.ceil is 3 puts 2.67.floor == 2 #=> true, because 2.67.floor is 2 

To make things of more sense here, you can convert results to Float:

(8.to_f / 3).ceil == 2  #=> false (8.to_f / 3).floor == 2 #=> true 2.67.ceil == 2          #=> false 2.67.floor == 2         #=> true 

Another thing to bear in mind, that having written 8/3.ceil is actually 8 / (3.ceil), because the . binds stronger than /. (thx @tadman)

Yet another thing to mention, is that (thx @Stefan):

There's also fdiv to perform floating point division, i.e. 8.fdiv(3).ceil. And Ruby also comes with a nice Rational class: (8/3r).ceil.