Comments on: Interesting behaviour in Ruby’s division and modulo operators http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/ Thoughts from the nice people at Codevader :) Thu, 11 Mar 2010 22:25:15 +0000 http://wordpress.org/?v=2.6.2 By: Mauricio Linhares http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-106 Mauricio Linhares Tue, 06 May 2008 14:49:12 +0000 http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-106 Well, it seems that everyone is correct (even my good old math teacher) -> http://en.wikipedia.org/wiki/Remainder#The_inequality_satisfied_by_the_remainder :) Well, it seems that everyone is correct (even my good old math teacher) -> http://en.wikipedia.org/wiki/Remainder#The_inequality_satisfied_by_the_remainder

:)

]]> By: Mauricio Linhares http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-104 Mauricio Linhares Tue, 06 May 2008 14:43:28 +0000 http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-104 Well, there doesn't seem to be a clear truth about this, nor Java neither Ruby is wrong (and not even my math teacher :D ) -> http://en.wikipedia.org/wiki/Modulo_operation Well, there doesn’t seem to be a clear truth about this, nor Java neither Ruby is wrong (and not even my math teacher :D ) -> http://en.wikipedia.org/wiki/Modulo_operation

]]> By: bandi http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-103 bandi Tue, 06 May 2008 14:00:07 +0000 http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-103 YoNoSoyTu is correct, integer division is not done via approximation. Consider the number 5. Integer division yields 5 = 1x3 + 2. You can see that the result is clearly 1, not 2. So you can see, that the 'floor' function is the appropriate way to describe what's going on. -7/3=2.333333... and if you take it's floor, you get -3 indeed. YoNoSoyTu is correct, integer division is not done via approximation. Consider the number 5. Integer division yields 5 = 1×3 + 2. You can see that the result is clearly 1, not 2. So you can see, that the ‘floor’ function is the appropriate way to describe what’s going on. -7/3=2.333333… and if you take it’s floor, you get -3 indeed.

]]> By: YoNoSoyTu http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-102 YoNoSoyTu Tue, 06 May 2008 08:33:24 +0000 http://blog.codevader.com/2008/05/06/interesting-behaviour-in-rubys-division-and-modulo-operators/#comment-102 That's because the division definition states that the remainder of a division should between 0 (inclusive) and |divisor| (absolute value), so, being your divisor 3, the remainder should be 0, 1, 2. So the solution of Ruby (or any other programming language with integer division) is correct. I think you should search your math teacher and gift he/she some basic algebra books. That’s because the division definition states that the remainder of a division should between 0 (inclusive) and |divisor| (absolute value), so, being your divisor 3, the remainder should be 0, 1, 2. So the solution of Ruby (or any other programming language with integer division) is correct.

I think you should search your math teacher and gift he/she some basic algebra books.

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