From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM
	autolearn=ham autolearn_force=no version=3.4.4
X-Google-Thread: 103376,2aaba1527862ef22
X-Google-Attributes: gid103376,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news2.google.com!news2.google.com!news.germany.com!border1.nntp.ams.giganews.com!nntp.giganews.com!news-in.ntli.net!newsrout1-win.ntli.net!ntli.net!news.highwinds-media.com!xara.net!gxn.net!194.159.246.34.MISMATCH!peer-uk.news.demon.net!kibo.news.demon.net!news.demon.co.uk!demon!not-for-mail
From: Simon Wright <simon.j.wright@mac.com>
Newsgroups: comp.lang.ada
Subject: Re: Reading Float Data from a binary file into ada
Date: Thu, 01 Feb 2007 21:11:26 +0000
Organization: Pushface
Message-ID: <m2d54t4m81.fsf@grendel.local>
References: <1170172307.292500.256090@m58g2000cwm.googlegroups.com>
 <45bf9b8b$0$22527$39db0f71@news.song.fi>
NNTP-Posting-Host: pogner.demon.co.uk
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Trace: news.demon.co.uk 1170364285 8083 62.49.19.209 (1 Feb 2007 21:11:25
 GMT)
X-Complaints-To: abuse@demon.net
NNTP-Posting-Date: Thu, 1 Feb 2007 21:11:25 +0000 (UTC)
Cancel-Lock: sha1:WaSHSkM2oWVqFvFw6RaQFUZm+WY=
User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.0.50 (darwin)
Xref: g2news2.google.com comp.lang.ada:8825
Date: 2007-02-01T21:11:26+00:00
List-Id: <comp.lang.ada>

Niklas Holsti <niklas.holsti@nospam.please> writes:

> - Use the functions Shift_Left or Shift_Right together with
>   the "or" operator (all from Interfaces) to assemble 4 octets
>   (Unsigned_8 values) into one 32-bit value of type
>   Interfaces.Unsigned_32. You may have to experiment to
>   get the octets in the right order.
>
> - Then use Unchecked_Conversion to go from Unsigned_32 to Float.

IF the VB view splits on octet boundaries, it can be easier to read
into an array of 4 octets (32 bits read), do the unchecked conversion
from array-of-4-octets to float with reordering; something like

  v : four_byte_array;
  function convert is new ada.unchecked_conversion (four_byte_array, float);

  read (v);
  result := convert ((1 => v (4), 2 => v (3), 3 => v (2); 4 => v (1)));

If not, why not read into unsigned_32 in the first place?