Nearest just interval: Difference between revisions

Wikispaces>xenwolf
**Imported revision 236918132 - Original comment: complementaries added to sqrt 2 approximation table**
Wikispaces>xenwolf
**Imported revision 236918684 - Original comment: links to some edos in table of approximations to 3:2**
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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
<h2>IMPORTED REVISION FROM WIKISPACES</h2>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
This is an imported revision from Wikispaces. The revision metadata is included below for reference:<br>
: This revision was by author [[User:xenwolf|xenwolf]] and made on <tt>2011-06-15 16:34:11 UTC</tt>.<br>
: This revision was by author [[User:xenwolf|xenwolf]] and made on <tt>2011-06-15 16:37:02 UTC</tt>.<br>
: The original revision id was <tt>236918132</tt>.<br>
: The original revision id was <tt>236918684</tt>.<br>
: The revision comment was: <tt>complementaries added to sqrt 2 approximation table</tt><br>
: The revision comment was: <tt>links to some edos in table of approximations to 3:2</tt><br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
The revision contents are below, presented both in the original Wikispaces Wikitext format, and in HTML exactly as Wikispaces rendered it.<br>
<h4>Original Wikitext content:</h4>
<h4>Original Wikitext content:</h4>
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||= 1 \ 2 || 1.0 ||= 600.00 ||= -101.96 ||
||= 1 \ 2 || 1.0 ||= 600.00 ||= -101.96 ||
||= 2 \ 3 || 2.585 ||= 800.00 ||= 98.045 ||
||= 2 \ 3 || 2.585 ||= 800.00 ||= 98.045 ||
||= 3 \ 5 || 3.907 ||= 720.00 ||= 18.045 ||
||= 3 \ [[5edo|5]] || 3.907 ||= 720.00 ||= 18.045 ||
||= 4 \ 7 || 4.807 ||= 685.7143 ||= -16.2407 ||
||= 4 \ [[7edo|7]] || 4.807 ||= 685.7143 ||= -16.2407 ||
||= 7 \ 12 || 6.392 ||= 700.00 ||= -1.955 ||
||= 7 \ [[12edo|12]] || 6.392 ||= 700.00 ||= -1.955 ||
||= 17 \ 29 || 8.945 ||= 703.4483 ||= 1.4933 ||
||= 17 \ [[29edo|29]] || 8.945 ||= 703.4483 ||= 1.4933 ||
||= 24 \ 41 || 9.943 ||= 702.43902 ||= 0.48402 ||</pre></div>
||= 24 \ [[41edo|41]] || 9.943 ||= 702.43902 ||= 0.48402 ||</pre></div>
<h4>Original HTML content:</h4>
<h4>Original HTML content:</h4>
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;Nearest just interval&lt;/title&gt;&lt;/head&gt;&lt;body&gt;An irrational interval or ratio of frequencies given by a real number r has an infinite list of &lt;em&gt;nearest just intervals&lt;/em&gt;; if r is rational, the list is finite, terminating in r. For arbitrary (including negative) real numbers this corresponds to what number theorists call &lt;em&gt;best rational approximations&lt;/em&gt;. A ratio of integers p/q with q &amp;gt; 0 and p and q relatively prime is a best rational approximation if there is no ratio m/n with n &amp;lt; q which is a better approximation to r. If r is an interval of music it is positive, and both p and q are positive. Note that a nearest just interval is not necessarily nearest in logarithmic terms; 4/3 and 3/2 are the same distance in cents from sqrt(2) = 600 cents, but |4/3 - sqrt(2)| = .08088 whereas |3/2 - sqrt(2)| = 0.08479, which is larger.&lt;br /&gt;
<div style="width:100%; max-height:400pt; overflow:auto; background-color:#f8f9fa; border: 1px solid #eaecf0; padding:0em"><pre style="margin:0px;border:none;background:none;word-wrap:break-word;width:200%;white-space: pre-wrap ! important" class="old-revision-html">&lt;html&gt;&lt;head&gt;&lt;title&gt;Nearest just interval&lt;/title&gt;&lt;/head&gt;&lt;body&gt;An irrational interval or ratio of frequencies given by a real number r has an infinite list of &lt;em&gt;nearest just intervals&lt;/em&gt;; if r is rational, the list is finite, terminating in r. For arbitrary (including negative) real numbers this corresponds to what number theorists call &lt;em&gt;best rational approximations&lt;/em&gt;. A ratio of integers p/q with q &amp;gt; 0 and p and q relatively prime is a best rational approximation if there is no ratio m/n with n &amp;lt; q which is a better approximation to r. If r is an interval of music it is positive, and both p and q are positive. Note that a nearest just interval is not necessarily nearest in logarithmic terms; 4/3 and 3/2 are the same distance in cents from sqrt(2) = 600 cents, but |4/3 - sqrt(2)| = .08088 whereas |3/2 - sqrt(2)| = 0.08479, which is larger.&lt;br /&gt;
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     &lt;/tr&gt;
     &lt;/tr&gt;
     &lt;tr&gt;
     &lt;tr&gt;
         &lt;td style="text-align: center;"&gt;3 \ 5&lt;br /&gt;
         &lt;td style="text-align: center;"&gt;3 \ &lt;a class="wiki_link" href="/5edo"&gt;5&lt;/a&gt;&lt;br /&gt;
&lt;/td&gt;
&lt;/td&gt;
         &lt;td&gt;3.907&lt;br /&gt;
         &lt;td&gt;3.907&lt;br /&gt;
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     &lt;/tr&gt;
     &lt;/tr&gt;
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         &lt;td style="text-align: center;"&gt;4 \ 7&lt;br /&gt;
         &lt;td style="text-align: center;"&gt;4 \ &lt;a class="wiki_link" href="/7edo"&gt;7&lt;/a&gt;&lt;br /&gt;
&lt;/td&gt;
&lt;/td&gt;
         &lt;td&gt;4.807&lt;br /&gt;
         &lt;td&gt;4.807&lt;br /&gt;
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     &lt;/tr&gt;
     &lt;/tr&gt;
     &lt;tr&gt;
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         &lt;td style="text-align: center;"&gt;7 \ 12&lt;br /&gt;
         &lt;td style="text-align: center;"&gt;7 \ &lt;a class="wiki_link" href="/12edo"&gt;12&lt;/a&gt;&lt;br /&gt;
&lt;/td&gt;
&lt;/td&gt;
         &lt;td&gt;6.392&lt;br /&gt;
         &lt;td&gt;6.392&lt;br /&gt;
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     &lt;/tr&gt;
     &lt;/tr&gt;
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         &lt;td style="text-align: center;"&gt;17 \ 29&lt;br /&gt;
         &lt;td style="text-align: center;"&gt;17 \ &lt;a class="wiki_link" href="/29edo"&gt;29&lt;/a&gt;&lt;br /&gt;
&lt;/td&gt;
&lt;/td&gt;
         &lt;td&gt;8.945&lt;br /&gt;
         &lt;td&gt;8.945&lt;br /&gt;
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     &lt;/tr&gt;
     &lt;/tr&gt;
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         &lt;td style="text-align: center;"&gt;24 \ 41&lt;br /&gt;
         &lt;td style="text-align: center;"&gt;24 \ &lt;a class="wiki_link" href="/41edo"&gt;41&lt;/a&gt;&lt;br /&gt;
&lt;/td&gt;
&lt;/td&gt;
         &lt;td&gt;9.943&lt;br /&gt;
         &lt;td&gt;9.943&lt;br /&gt;