/usr/share/doc/axiom-doc/hypertex/conversionfunctions.xhtml

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 <body>
  <div align="center"><img align="middle" src="doctitle.png"/></div>
  <hr/>
  <div align="center">Conversion Functions</div>
  <hr/>
You can use conversion (see 
<a href="axbook/section-9.27.xhtml#subsec-9.27.2">Jenks section 9.27.2</a>)
to go back and forth between
<a href="db.xhtml?Integer">Integer</a>,
<a href="db.xhtml?Fraction(Integer)">Fraction(Integer)</a> and
<a href="db.xhtml?Float">Float</a>, as appropriate.
<ul>
 <li>
  <input type="submit" id="p1" class="subbut" 
    onclick="makeRequest('p1');"
    value="i:=3::Float" />
  <div id="ansp1"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p2" class="subbut" 
    onclick="handleFree(['p1','p2']);"
    value="i::Integer" />
  <div id="ansp2"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p3" class="subbut" 
    onclick="handleFree(['p1','p3']);"
    value="i::Fraction Integer" />
  <div id="ansp3"><div></div></div>
 </li>
</ul>
Since you are explicitly asking for a conversion, you must take 
responsibility for any loss of exactness.
<ul>
 <li>
  <input type="submit" id="p4" class="subbut" 
    onclick="makeRequest('p4');"
    value="r:=3/7::Float" />
  <div id="ansp4"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p5" class="subbut" 
    onclick="handleFree(['p4','p5']);"
    value="r::Fraction Integer" />
  <div id="ansp5"><div></div></div>
 </li>
</ul>
This conversion cannot be performed: use 
<a href="dboptruncate.xhtml">truncate</a> or
<a href="dbopround.xhtml">round</a> if that is what you intend.
<ul>
 <li>
  <input type="submit" id="p6" class="subbut" 
    onclick="handleFree(['p4','p6']);"
    value="r::Integer" />
  <div id="ansp6"><div></div></div>
 </li>
</ul>
The operations
<a href="dboptruncate.xhtml">truncate</a> and
<a href="dbopround.xhtml">round</a> truncate ...
<ul>
 <li>
  <input type="submit" id="p7" class="subbut" 
    onclick="makeRequest('p7');"
    value="truncate 3.6" />
  <div id="ansp7"><div></div></div>
 </li>
</ul>
and round to the nearest integral <a href="db.xhtml?Float">Float</a>
respectively.
<ul>
 <li>
  <input type="submit" id="p8" class="subbut" 
    onclick="makeRequest('p8');"
    value="round 3.6" />
  <div id="ansp8"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p9" class="subbut" 
    onclick="makeRequest('p9');"
    value="truncate(-3.6)" />
  <div id="ansp9"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p10" class="subbut" 
    onclick="makeRequest('p10');"
    value="round(-3.6)" />
  <div id="ansp10"><div></div></div>
 </li>
</ul>
The operation <a href="dbopfractionpart.xhtml">fractionPart</a>
computes the fractional part of x, that is, x-truncate x.
<ul>
 <li>
  <input type="submit" id="p11" class="subbut" 
    onclick="makeRequest('p11');"
    value="fractionPart 3.6" />
  <div id="ansp11"><div></div></div>
 </li>
</ul>
The operation <a href="dbopdigits.xhtml">digits</a> allows the user to
set the precision. It returns the previous value it was using.
<ul>
 <li>
  <input type="submit" id="p12" class="subbut" 
    onclick="makeRequest('p12');"
    value="digits 40" />
  <div id="ansp12"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p13" class="subbut" 
    onclick="makeRequest('p13');"
    value="sqrt 0.2" />
  <div id="ansp13"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p14" class="subbut" 
    onclick="makeRequest('p14');"
    value="pi()$Float" />
  <div id="ansp14"><div></div></div>
 </li>
</ul>
The precision is only limited by the computer memory available.
Calculations at 500 or more digits of precision are not difficult.
<ul>
 <li>
  <input type="submit" id="p15" class="subbut" 
    onclick="makeRequest('p15');"
    value="digits 500" />
  <div id="ansp15"><div></div></div>
 </li>
 <li>
  <input type="submit" id="p16" class="subbut" 
    onclick="makeRequest('p16');"
    value="pi()$Float" />
  <div id="ansp16"><div></div></div>
 </li>
</ul>
Reset <a href="dbopdigits.xhtml">digits</a> to its default value.
<ul>
 <li>
  <input type="submit" id="p17" class="subbut" 
    onclick="makeRequest('p17');"
    value="digits 20" />
  <div id="ansp17"><div></div></div>
 </li>
</ul>
Numbers of type <a href="db.xhtml?Float">Float</a> are represented as a record
of two integers, namely, the mantissa and the exponent where the base
of the exponent is binary. That is, the floating point number of the
binary. That is, the floating point number (m,e) represents the number
m*2**e. A consequence of using a binary base is that decimal numbers
can not, in general, be represented exactly.
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axiom-hypertex-data 20120501-8 / usr / share / doc / axiom-doc / hypertex / conversionfunctions.xhtml
