Ruby on Rails decimal column

Question

If you specify your ActiveRecord column type to be decimal, Rails will return that database value as a ruby BigDecimal object.

My question is, when working with these fields and performing additional math on them, should I always use BigDecimal values in my calculations or are floating point values ok to use. I didn't know if it is a good practice to be mixing BigDecimal values and Floating Point values in the same calculations.

Mixed Example: BigDecimal.new('12.43') / 4.2

Same type Example: BigDecimal.new('12.43') / BigDecimal.new('4.2')

The reason I ask is because I'm a little gun shy of using floats because I need decimal accuracy. 0.1 + 0.7 will not equal 0.8 using floats.

Answer 1

stumbled across this article, it makes some good points for using BigDecimal

http://ramblingsof.justinwinkler.com/when-crap-just-doesnt-add-up

Answer 2

Since you're

... a little gun shy of using floats...

use BigDecimal. Works fine