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<p>Here is the spec they are referencing in this thread:
<a class="moz-txt-link-freetext" href="https://stackoverflow.com/questions/4975005/how-should-i-interpret-the-asn-1-ber-standard-for-reals">https://stackoverflow.com/questions/4975005/how-should-i-interpret-the-asn-1-ber-standard-for-reals</a></p>
<p><br>
</p>
<p><a class="moz-txt-link-freetext" href="https://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#%5B%7B%22num%22%3A41%2C%22gen%22%3A0%7D%2C%7B%22name%22%3A%22FitH%22%7D%2C519%5D">https://www.itu.int/ITU-T/studygroups/com17/languages/X.690-0207.pdf#%5B%7B%22num%22%3A41%2C%22gen%22%3A0%7D%2C%7B%22name%22%3A%22FitH%22%7D%2C519%5D</a><br>
</p>
<br>
<div class="moz-cite-prefix">On 10/12/2017 05:36 AM, Alan Pinch
wrote:<br>
</div>
<blockquote type="cite"
cite="mid:77ab2564-1ed5-0adf-99f0-f72f1e8e280c@gmail.com">
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<p>The same issue exists in ASN1 support, none for float type tag
9. I would love to add this support but I am unsure how to
breakdown a float into mantissa, base and exponent. Here is a
description of how ASN1 formats a REAL into the stream of bytes:<br>
</p>
<blockquote>Type REAL takes values that are the machine
representation of a real number, namely the triplet (m, b, e),
where m is the mantissa (a signed number), b the base (2 or 10),
and e the exponent (a signed number). For example, the
representation of the value 3.14 for the variable Pi, declared
as Pi ::= REAL, can be (314, 10, -2). Three special values,
PLUS-INFINITY, 0, and MINUS-INFINITY, are also allowed.</blockquote>
Here are some sample values:<br>
<blockquote>
<ul>
<li>09 00 = 0 (zero)</li>
<li>09 01 40 = +INF (infinity)</li>
<li>09 01 41 = -INF</li>
<li>09 08 03 2b 31 2e 30 65 2b 30 = "+1.0e+0" = 1.0 (exact
decimal)</li>
<li>09 05 80 fe 55 55 55 = 1398101.25 (binary, 0x555555 *
2^-2)</li>
<li>09 06 83 00 fc 00 00 01 = 0.0625 (binary, 0x000001 * 2^-4)<br>
</li>
</ul>
</blockquote>
I have not parsed out these samples into these components so it's
greek.<br>
<br>
Alan<br>
<br>
<div class="moz-cite-prefix">On 10/11/2017 02:18 PM, Bert
Freudenberg wrote:<br>
</div>
<blockquote type="cite"
cite="mid:CACnEXefzh7MguY=Tf69+xRG+aEsQEL3_Y0pwF6-ZTM37mnfBiQ@mail.gmail.com">
<div dir="ltr">
<div class="gmail_default"
style="font-family:arial,helvetica,sans-serif;font-size:small;color:#000000"><span
style="font-family:arial,sans-serif;color:rgb(34,34,34)">On
Wed, Oct 11, 2017 at 8:07 PM, Tobias Pape </span><span
dir="ltr"
style="font-family:arial,sans-serif;color:rgb(34,34,34)"><<a
href="mailto:Das.Linux@gmx.de" target="_blank"
moz-do-not-send="true">Das.Linux@gmx.de</a>></span><span
style="font-family:arial,sans-serif;color:rgb(34,34,34)">
wrote:</span><br>
</div>
<div class="gmail_extra">
<div class="gmail_quote">
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex"><span
class=""><br>
> On 11.10.2017, at 19:59, Bert Freudenberg <<a
href="mailto:bert@freudenbergs.de"
moz-do-not-send="true">bert@freudenbergs.de</a>>
wrote:<br>
><br>
> On Wed, Oct 11, 2017 at 5:24 PM, Tobias Pape <<a
href="mailto:Das.Linux@gmx.de"
moz-do-not-send="true">Das.Linux@gmx.de</a>>
wrote:<br>
> Hi all<br>
><br>
> I'm a bit stumped…<br>
><br>
> What is our canonical way to put a Float onto a
(binary) stream?<br>
> To be precise a IEEE754 double precision 64-bit
float onto a stream, of which I only know that it is a
binary one.<br>
><br>
> I found ByteArray>>doubleAt:{put:}<wbr>bigEndian:,
but they have neither senders nor test _and_ it is not
a stream.<br>
><br>
> What do y'all use?<br>
><br>
> You write them as two words, like e.g. in
DataStream>>writeFloat:.<br>
<br>
</span>Quite. yes.<br>
<br>
But I find it strange that our read/write streams
support various integer and string reading/writing
helpers, but none for floats…<br>
<br>
Best regards<br>
<span class="HOEnZb"><font color="#888888">
-Tobias<br>
</font></span></blockquote>
<div><br>
</div>
<div class="gmail_default"
style="font-family:arial,helvetica,sans-serif;font-size:small;color:rgb(0,0,0)">I
guess file formats using integers and strings are way
more common than ones storing binary floats.</div>
<div class="gmail_default"
style="font-family:arial,helvetica,sans-serif;font-size:small;color:rgb(0,0,0)"><br>
</div>
<div class="gmail_default"
style="font-family:arial,helvetica,sans-serif;font-size:small;color:rgb(0,0,0)">-
Bert -</div>
</div>
</div>
</div>
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<br>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Thank you for your consideration,
Alan
</pre>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Thank you for your consideration,
Alan
</pre>
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