Issue #9316 has been updated by al2o3cr (Matt Jones).


Still fuzzy on the cause, but the behavior is interesting - it appears that something has changed regarding the way that non-terminating decimals are rounded.

There's also some magnitude-dependent behavior: 147.2 / 0.099 (and related variants shifting the decimals around) don't always return the same value.

Here's a little program to compare the behavior for different offsets:

https://gist.github.com/al2o3cr/8175722

Attached to that are also the results of running the script on 2.0.0 and 2.1.0. 

----------------------------------------
Bug #9316: BigDecimal division in Ruby 2.1
https://bugs.ruby-lang.org/issues/9316#change-43952

Author: abernardes (Andre Bernardes)
Status: Assigned
Priority: Normal
Assignee: mrkn (Kenta Murata)
Category: lib
Target version: current: 2.2.0
ruby -v: ruby 2.1.0p0 (2013-12-25 revision 44422) [x86_64-darwin13.0]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN, 2.1: UNKNOWN


=begin
When updating an app to Ruby 2.1, and I ran into the following difference between ruby 2.0.0-p353 and ruby 2.1.0 when dividing two BigDecimals:

((*Ruby 2.0.0p353:*))
 2.0.0p353 :002 > (BigDecimal.new("1472.0") / BigDecimal.new("0.99")).to_f
  => 1486.868686869

((*Ruby 2.1.0p0:*))
 2.1.0p0 :006 > (BigDecimal.new("1472.0") / BigDecimal.new("0.99")).to_f
  => 1487.0
=end


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