Popular recipes tagged "meta:requires=fractions"http://code.activestate.com/recipes/tags/meta:requires=fractions/2013-12-27T06:43:59-08:00ActiveState Code RecipesPublic Key Encryption (RSA) (Python)
2013-12-27T06:43:59-08:00Mohammad Taha Jahangirhttp://code.activestate.com/recipes/users/4188847/http://code.activestate.com/recipes/578797-public-key-encryption-rsa/
<p style="color: grey">
Python
recipe 578797
by <a href="/recipes/users/4188847/">Mohammad Taha Jahangir</a>
(<a href="/recipes/tags/encryption/">encryption</a>, <a href="/recipes/tags/inverse/">inverse</a>, <a href="/recipes/tags/multiplicative/">multiplicative</a>, <a href="/recipes/tags/primality_testing/">primality_testing</a>, <a href="/recipes/tags/primes/">primes</a>, <a href="/recipes/tags/publickey/">publickey</a>, <a href="/recipes/tags/rsa/">rsa</a>).
Revision 3.
</p>
<p>Simple code to create and use public/private keypairs. Accompanied by a rudimentary encoder.</p>
Continued fractions (Python)
2013-08-22T07:15:47-07:00Glenn Hutchingshttp://code.activestate.com/recipes/users/4175415/http://code.activestate.com/recipes/578647-continued-fractions/
<p style="color: grey">
Python
recipe 578647
by <a href="/recipes/users/4175415/">Glenn Hutchings</a>
(<a href="/recipes/tags/decimal/">decimal</a>, <a href="/recipes/tags/fractions/">fractions</a>).
Revision 2.
</p>
<p>A class representing a <a href="https://en.wikipedia.org/wiki/Continued_fraction">continued fraction</a>.</p>
Public Key Encryption (RSA) (Python)
2012-05-12T23:34:22-07:00Raymond Hettingerhttp://code.activestate.com/recipes/users/178123/http://code.activestate.com/recipes/577737-public-key-encryption-rsa/
<p style="color: grey">
Python
recipe 577737
by <a href="/recipes/users/178123/">Raymond Hettinger</a>
(<a href="/recipes/tags/encryption/">encryption</a>, <a href="/recipes/tags/inverse/">inverse</a>, <a href="/recipes/tags/multiplicative/">multiplicative</a>, <a href="/recipes/tags/primality_testing/">primality_testing</a>, <a href="/recipes/tags/primes/">primes</a>, <a href="/recipes/tags/publickey/">publickey</a>, <a href="/recipes/tags/rsa/">rsa</a>).
Revision 2.
</p>
<p>Simple code to create and use public/private keypairs. Accompanied by a rudimentary encoder.</p>
Generate equally-spaced floats (Python)
2011-09-24T18:49:39-07:00Steven D'Apranohttp://code.activestate.com/recipes/users/4172944/http://code.activestate.com/recipes/577878-generate-equally-spaced-floats/
<p style="color: grey">
Python
recipe 577878
by <a href="/recipes/users/4172944/">Steven D'Aprano</a>
(<a href="/recipes/tags/float/">float</a>, <a href="/recipes/tags/range/">range</a>, <a href="/recipes/tags/spread/">spread</a>).
</p>
<p>Generating a list of equally-spaced floats can surprising due to floating point rounding. See, for example, the recipe for a <a href="http://code.activestate.com/recipes/577068">floating point range</a>. One way of avoiding some surprises is by changing the API: instead of specifying a start, stop and step values, instead use a start, stop and count:</p>
<pre class="prettyprint"><code>>>> list(spread(0.0, 2.1, 7))
[0.0, 0.3, 0.6, 0.9, 1.2, 1.5, 1.8]
</code></pre>
<p>Like <a href="http://code.activestate.com/recipes/577068">frange</a> <code>spread</code> takes an optional mode argument to select whether the start and end values are included. By default, start is included and end is not, and exactly count values are returned.</p>
Equally-spaced floats part 2 (Python)
2011-09-27T15:48:00-07:00Steven D'Apranohttp://code.activestate.com/recipes/users/4172944/http://code.activestate.com/recipes/577881-equally-spaced-floats-part-2/
<p style="color: grey">
Python
recipe 577881
by <a href="/recipes/users/4172944/">Steven D'Aprano</a>
(<a href="/recipes/tags/float/">float</a>, <a href="/recipes/tags/range/">range</a>, <a href="/recipes/tags/spread/">spread</a>).
</p>
<p>See the recipe <a href="http://code.activestate.com/recipes/577878">here</a> for a description of the problem.</p>
<p>This variant allows the user to choose between two APIs, either by supplying the count, start value and end value:</p>
<pre class="prettyprint"><code>>>> list(spread(5, 1.0, end=2.0))
[1.0, 1.2, 1.4, 1.6, 1.8]
</code></pre>
<p>or the count, start value and step size:</p>
<pre class="prettyprint"><code>>>> list(spread(5, 1.0, step=-0.25))
[1.0, 0.75, 0.5, 0.25, 0.0]
</code></pre>
<p>As before, the count argument specifies how many subdivisions are made. The optional argument <code>mode</code> selects whether the start and end values are included. By default, start is included and end is not, and exactly count values are returned.</p>
Binary floating point summation accurate to full precision (Python)
2009-03-28T23:32:08-07:00Raymond Hettingerhttp://code.activestate.com/recipes/users/178123/http://code.activestate.com/recipes/393090-binary-floating-point-summation-accurate-to-full-p/
<p style="color: grey">
Python
recipe 393090
by <a href="/recipes/users/178123/">Raymond Hettinger</a>
(<a href="/recipes/tags/algorithms/">algorithms</a>).
Revision 5.
</p>
<p>Completely eliminates rounding errors and loss of significance due to catastrophic cancellation during summation. Achieves exactness by keeping full precision intermediate subtotals. Offers three alternative approaches, each using a different technique to store exact subtotals.</p>