Re: Question about Float

[Martin <martin.dowie@btopenworld.com>]

On 3 Dec, 10:18, Ludovic Brenta <ludo...@ludovic-brenta.org> wrote:
> axtens writes:
> > G'day everyone,
>
> > What is the size/precision of a Float in Ada? Under GNAT/GCC it
> > appears to be equivalent to a VB6 Single. Under ObjectAda is appears
> > to be a full 8 byter, similar to VB6's Double. But is it?
>
> > I'm confused.
>
> The range and precision of Float are implementation-defined and change
> between e.g. 32-bit, 64-bit platforms and Intel platforms where there
> is a 80-bit floating-point type and PowerPC that has a 128-bit
> floating-point type.  Therefore you should not use Float.  Define your
> own floating-point type such that its representation matches that of
> Visual Basic.

Surely you mean " Define your own floating-point type such that its
accuracy requirements are met"? e.g.

type Real is digits 7;  -- or 8 or 10 or whatever your app requires?

If you are interfacing with an 'outside world' (e.g. a .dll) you can
define wrappers in terms of types defined in standard "package
Interfaces".

Cheers
-- Martin