Re: RFA/PATCH gtest - NSNumber float != double

[David Ayers]

Alexander Malmberg wrote:

> David Ayers wrote:
>  
>
> > Hello everyone,
> >
> > I'm working on a set of GDL2 guile tests and ran into a base issue.
> > +numberWithFloat: 25.1 and +numberWithDouble: 25.1 are not equal.  I've
> > attached an patch for gtest on this issue which also updates some other
> > changes in the general configuration.
> >    
>
> This is expected. 25.1 can not be represented exactly as a floating
> point number. When you create a float 25.1, you get the float-number
> closest to 25.1, and when you create a double 25.1, you get the
> double-number closest to 25.1. These usually aren't the same, so the
> comparison is correct.
>
>  
Hmm, I'll take your word  for it.  I just recalled back in the dark ages 
someone told me (or I read it somewhere) that 25.1 would somehow be 
represented as 2.51 * 10^1 and that a float or double only stored the 
mantissa and exponent which shouldn't result in any discrepancies here.  
But maybe that was just some illustration of principle. (I wonder how 
Apple deals with this... I'll check tomorrow.)

Thanx,
Dave