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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Newsgroups: comp.lang.ada
Subject: Re: 32-bit float and 64-bit float
Date: Mon, 14 Aug 2017 08:55:19 +0200
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Date: 2017-08-14T08:55:19+02:00
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On 14/08/2017 00:29, Victor Porton wrote:
> What is the best way to define in Ada types which are expected to contain:
> 
> 1. 64-bit floating point numbers (incl. ±Inf, ±0, NaN);
> 
> 2. 32-bit floating point numbers (incl. ±Inf, ±0, NaN).

There is no way since you specified neither the precision and range nor 
the floating-point representation format IEEE 754, IBM, DEC etc.

Ada's way is the former. The latter is not possible in general.

If you have a requirement to support a specific representation, e.g. for 
I/O you have to convert it forth and back to an Ada type most close to 
it. In Simple Components there are packages to convert IEEE 754 floats:

http://www.dmitry-kazakov.de/ada/components.htm#IEEE_754

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de