Topic: Force calculation result to BigDecimal
I'm doing some complex math which I need to be based on BigDecimal accuracy (not Float). It seems that ruby defaults to Float when there's a mixture of type in there, e.g.
irb(main):001:0> require 'bigdecimal'
irb(main):002:0> a = 5.123
irb(main):003:0> b = BigDecimal("6.789")
irb(main):004:0> c = a * b
Is there a way I can force a BigDecimal outcome.
One way I guess would work is to make sure all args in the calculation are BigDecimal, but that's a bit tiresome. For a start, I'd have to type check each arg and convert to BigDecimal if it was not BigDecimal - that's gotta be slow...
On a related note, how do I initalize a BigDecimal from a Float (without converting to string first). How could I extend BigDecimal for this?