Consistency: Difference between revisions

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<h2>IMPORTED REVISION FROM WIKISPACES</h2>
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: This revision was by author [[User:xenwolf|xenwolf]] and made on <tt>2011-06-29 04:05:08 UTC</tt>.<br>
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== Examples ==
== Examples ==
An example for a system that is not consistent is [[25edo]]:
An example for a system that is //not// consistent in a particular odd limit is [[25edo]]:


The best approximation for the interval of [[7_6|7/6]] (the septimal subminor third) in 25edo is 6 steps, the best approximation for the [[3_2|perfect fifth 3/2]] is 15 steps.
The best approximation for the interval of [[7_6|7/6]] (the septimal subminor third) in 25edo is 6 steps, the best approximation for the [[3_2|perfect fifth 3/2]] is 15 steps.
Adding the two just intervals gives 3/2 * 7/6 = [[7_4|7/4]], the harmonic seventh, for which the best approximation in 25edo is 20 steps. Adding the two approximated intervals, however, gives 21 steps. This means that 25edo is not consistent in [[7-limit]].
Adding the two just intervals gives 3/2 * 7/6 = [[7_4|7/4]], the harmonic seventh, for which the best approximation in 25edo is 20 steps. Adding the two approximated intervals, however, gives 21 steps. This means that 25edo is not consistent in [[7-limit]].


An example for a system that is consistent in the 3-limit is [[12edo]]: the (up to 12) multiples of the just fifth ([[3_2|3:2]]) are consistently approximated by the 12-edo steps.
An example for a system that //is// consistent in the 3-limit is [[12edo]]: the (up to 12) multiples of the just fifth ([[3_2|3:2]]) are consistently approximated by the 12-edo steps.


== Links ==
== Links ==
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&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc0"&gt;&lt;a name="x-Examples"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt; Examples &lt;/h2&gt;
&lt;!-- ws:start:WikiTextHeadingRule:0:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc0"&gt;&lt;a name="x-Examples"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:0 --&gt; Examples &lt;/h2&gt;
An example for a system that is not consistent is &lt;a class="wiki_link" href="/25edo"&gt;25edo&lt;/a&gt;:&lt;br /&gt;
An example for a system that is &lt;em&gt;not&lt;/em&gt; consistent in a particular odd limit is &lt;a class="wiki_link" href="/25edo"&gt;25edo&lt;/a&gt;:&lt;br /&gt;
&lt;br /&gt;
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The best approximation for the interval of &lt;a class="wiki_link" href="/7_6"&gt;7/6&lt;/a&gt; (the septimal subminor third) in 25edo is 6 steps, the best approximation for the &lt;a class="wiki_link" href="/3_2"&gt;perfect fifth 3/2&lt;/a&gt; is 15 steps.&lt;br /&gt;
The best approximation for the interval of &lt;a class="wiki_link" href="/7_6"&gt;7/6&lt;/a&gt; (the septimal subminor third) in 25edo is 6 steps, the best approximation for the &lt;a class="wiki_link" href="/3_2"&gt;perfect fifth 3/2&lt;/a&gt; is 15 steps.&lt;br /&gt;
Adding the two just intervals gives 3/2 * 7/6 = &lt;a class="wiki_link" href="/7_4"&gt;7/4&lt;/a&gt;, the harmonic seventh, for which the best approximation in 25edo is 20 steps. Adding the two approximated intervals, however, gives 21 steps. This means that 25edo is not consistent in &lt;a class="wiki_link" href="/7-limit"&gt;7-limit&lt;/a&gt;.&lt;br /&gt;
Adding the two just intervals gives 3/2 * 7/6 = &lt;a class="wiki_link" href="/7_4"&gt;7/4&lt;/a&gt;, the harmonic seventh, for which the best approximation in 25edo is 20 steps. Adding the two approximated intervals, however, gives 21 steps. This means that 25edo is not consistent in &lt;a class="wiki_link" href="/7-limit"&gt;7-limit&lt;/a&gt;.&lt;br /&gt;
&lt;br /&gt;
&lt;br /&gt;
An example for a system that is consistent in the 3-limit is &lt;a class="wiki_link" href="/12edo"&gt;12edo&lt;/a&gt;: the (up to 12) multiples of the just fifth (&lt;a class="wiki_link" href="/3_2"&gt;3:2&lt;/a&gt;) are consistently approximated by the 12-edo steps.&lt;br /&gt;
An example for a system that &lt;em&gt;is&lt;/em&gt; consistent in the 3-limit is &lt;a class="wiki_link" href="/12edo"&gt;12edo&lt;/a&gt;: the (up to 12) multiples of the just fifth (&lt;a class="wiki_link" href="/3_2"&gt;3:2&lt;/a&gt;) are consistently approximated by the 12-edo steps.&lt;br /&gt;
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&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc1"&gt;&lt;a name="x-Links"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt; Links &lt;/h2&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h2&amp;gt; --&gt;&lt;h2 id="toc1"&gt;&lt;a name="x-Links"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt; Links &lt;/h2&gt;
&lt;a class="wiki_link_ext" href="http://www.tonalsoft.com/enc/c/consistent.aspx" rel="nofollow"&gt;consistent (TonalSoft encyclopedia)&lt;/a&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>
&lt;a class="wiki_link_ext" href="http://www.tonalsoft.com/enc/c/consistent.aspx" rel="nofollow"&gt;consistent (TonalSoft encyclopedia)&lt;/a&gt;&lt;/body&gt;&lt;/html&gt;</pre></div>