[Python-ideas] Python Numbers as Human Concept Decimal System

[Antoine Pitrou]

On Sat, 08 Mar 2014 01:14:46 -0500
Terry Reedy <tjreedy at udel.edu> wrote:
> On 3/7/2014 2:20 PM, Guido van Rossum wrote:
> 
> 
> > However, for the growing contingent of scientists who use Python as a
> > replacement for Matlab (not Mathematica!), it could be a big nuisance.
> > They don't care about decimal issues (they actually like binary better)
> 
> One reason knowledgeable users of floating point numbers as 
> approximations like binary better is that the binary floating point 
> system is much 'smoother' than the decimal floating point system. For 
> example, with 3 decimal digits, consider .999, 1.00, 1.01. The first 
> difference is .001, the second is .01, 10 x larger.  This is one of the 
> problems of working with base 10 slide rules. For binary, the largest 
> ratio between differences is 2 rather than 10.

Well, can you explain what difference it does in practice?

Regards

Antoine.