Bug #9691: Wrong value on float

• Status: Rejected
• Assignee: -
• Target version: -
• ruby -v: 2.1.0
• Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN

Getting strange value on multiplying a float

149.95 * 100
=> 14994.999999999998

[shyouhei (Shyouhei Urabe)]

• Status changed from Open to Rejected

This is how it works. Learn floating point numbers.

"What Every Computer Scientist Should Know About Floating-Point Arithmetic"
http://docs.sun.com/source/806-3568/ncg_goldberg.html

[avit (Andrew Vit)]

Use Fixnum (14995 * 100) or BigDecimal:

require 'bigdecimal'
d = BigDecimal.new('149.95')
d * 100
# => 0.14995E5

More info on floating point vs. decimal numbers:
http://www.youtube.com/watch?v=PZRI1IfStY0