I'm doing some math with Ruby and I'd really like to know why:
irb(main):002:0> 10.0 / 3.0
=> 3.33333333333333
but
irb(main):003:0> (10.0 / 3.0) == 3.33333333333333
is
=> false
Thanks 
Cliff
This is because the 3.33333333333333 is not the exact value you got
from 10.0/3.0. Ruby store more information you can't not see.
So if you want to compare the float, you can write it as
(10.0/3.0 - 3.3333333333).abs <= 0.0001
路路路
On Aug 11, 10:10 am, Cliff Rowley <cliffrow...@gmail.com> wrote:
I'm doing some math with Ruby and I'd really like to know why:
irb(main):002:0> 10.0 / 3.0
=> 3.33333333333333but
irb(main):003:0> (10.0 / 3.0) == 3.33333333333333
is
=> false
Thanks
Cliff
Hank Gong wrote:
This is because the 3.33333333333333 is not the exact value you got
from 10.0/3.0. Ruby store more information you can't not see.
So if you want to compare the float, you can write it as
(10.0/3.0 - 3.3333333333).abs <= 0.0001
This is what I thought. Thanks for clarifying that. I need it primarily for unit testing, I'll try this technique and see how I go.
Thanks again
Cliff
assert_in_delta 3.3333333333, 10.0/3.0, 0.0001
-greg
路路路
On 8/10/07, Cliff Rowley <cliffrowley@gmail.com> wrote:
Hank Gong wrote:
> This is because the 3.33333333333333 is not the exact value you got
> from 10.0/3.0. Ruby store more information you can't not see.
> So if you want to compare the float, you can write it as
> (10.0/3.0 - 3.3333333333).abs <= 0.0001
>
This is what I thought. Thanks for clarifying that. I need it
primarily for unit testing, I'll try this technique and see how I go.
Gregory Brown wrote:
assert_in_delta 3.3333333333, 10.0/3.0, 0.0001
-greg
Perfect, thankyou 
Cliff