Recoverability: Difference between revisions
Wikispaces>genewardsmith **Imported revision 540092618 - Original comment: ** |
Wikispaces>genewardsmith **Imported revision 540094842 - Original comment: ** |
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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:genewardsmith|genewardsmith]] and made on <tt>2015-02-07 12: | : This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2015-02-07 12:58:38 UTC</tt>.<br> | ||
: The original revision id was <tt> | : The original revision id was <tt>540094842</tt>.<br> | ||
: The revision comment was: <tt></tt><br> | : The revision comment was: <tt></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> | ||
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=The rank one case= | =The rank one case= | ||
In the case of rank one, if W is an N-edo val, ie whose first coefficient is N. then W∨2 = N and (W∨2)∧J = NJ, so that rounding it gives the patent val for N. Hence, W is recoverable if and only if it is a patent val. However, ]W∧J[ < 600 cents is now a stringent condition for p>5, especially in higher prime limits. In the 5-limit we have 4, 5, 7, 8, 12, 15, 19, 22, 23, 26, 27, 31, 34 ... . The 7-limit grows somewhat restrictive: 19, 27, 31, 41, 49, 60, 68, 72, 80, 91, 99... . In the 11-limit we have 49, 72, 103, 239, 270, 342, 391, 414, 445, 494, 552, 612... . The 13-limit is already quite restrictive: 552, 954, 1133, 1236, 1506..., and the 17-limit starts off 4452, 5527, 7033, 7315, 9896... . | In the case of rank one, if W is an N-edo val, ie whose first coefficient is N. then W∨2 = N and (W∨2)∧J = NJ, so that rounding it gives the patent val for N. Hence, W is recoverable if and only if it is a patent val. However, ]W∧J[ < 600 cents is now a stringent condition for p>5, especially in higher prime limits. In the 5-limit we have 4, 5, 7, 8, 12, 15, 19, 22, 23, 26, 27, 31, 34 ... . The 7-limit grows somewhat restrictive: 19, 27, 31, 41, 49, 60, 68, 72, 80, 91, 99... . In the 11-limit we have 49, 72, 103, 239, 270, 342, 391, 414, 445, 494, 552, 612... . The 13-limit is already quite restrictive: 552, 954, 1133, 1236, 1506..., and the 17-limit starts off 4452, 5527, 7033, 7315, 9896... . | ||
If W is the patent val for N-edo and ]W∧J[ > 600 cents, it can happen that the minimum value for recoverability relative error/simple badness, defined as ]V∧J[ for any N-edo val V, does not occur for V = W. Examples are 13-limit 12f, where ]12f∧J[ = 1217.949 is much smaller than ]12∧J[ = 3844.172, 5-limit 17c, ]17c∧J[ = 847.730 compared to ]17∧J[ = 1054.225, and 11-limit 27e, where ]27e∧J[ = 1169.472 is less than ]27∧J[ = 2405.855. Of course two possibilities can be close enough that both are plausible, as with 7-limit 34d at 1169.472 cents versus 34 at 1437.444 cents. | |||
=Complete searches for temperaments= | =Complete searches for temperaments= | ||
By a complete search for regular temperaments is meant a search which is guaranteed to find all temperaments meeting certain specified conditions. Recoverability conditions provide one approach to these. The first segment of W∨2 consists of C(n-1, r-1) zeros, and the second segment of C(n-1, r) integers identical to the initial, 2 containing, segment of W. By beginning with such a multivector of integer coefficients, wedging with J, and rounding, we obtain a multivector which is a candidate for a p-limit rank r wedgie, defining a regular temperament. It will not in general be a wedgie, but all recoverable wedgies can be obtained in this way. Hence all that remains to do, as discussed in [[The wedgie]], is to test if the multivector in question is actually a wedgie, and also if it passes any further conditions on complexity, error of badness we wish to place on our list of wedgies. | By a complete search for regular temperaments is meant a search which is guaranteed to find all temperaments meeting certain specified conditions. Recoverability conditions provide one approach to these. The first segment of W∨2 consists of C(n-1, r-1) zeros, and the second segment of C(n-1, r) integers identical to the initial, 2 containing, segment of W. By beginning with such a multivector of integer coefficients, wedging with J, and rounding, we obtain a multivector which is a candidate for a p-limit rank r wedgie, defining a regular temperament. It will not in general be a wedgie, but all recoverable wedgies can be obtained in this way. Hence all that remains to do, as discussed in [[The wedgie]], is to test if the multivector in question is actually a wedgie, and also if it passes any further conditions on complexity, error of badness we wish to place on our list of wedgies.</pre></div> | ||
</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"><html><head><title>Recoverability</title></head><body><!-- ws:start:WikiTextTocRule:10:&lt;img id=&quot;wikitext@@toc@@flat&quot; class=&quot;WikiMedia WikiMediaTocFlat&quot; title=&quot;Table of Contents&quot; src=&quot;/site/embedthumbnail/toc/flat?w=100&amp;h=16&quot;/&gt; --><!-- ws:end:WikiTextTocRule:10 --><!-- ws:start:WikiTextTocRule:11: --><a href="#Definition">Definition</a><!-- ws:end:WikiTextTocRule:11 --><!-- ws:start:WikiTextTocRule:12: --> | <a href="#Segments">Segments</a><!-- ws:end:WikiTextTocRule:12 --><!-- ws:start:WikiTextTocRule:13: --> | <a href="#The recoverability norm">The recoverability norm</a><!-- ws:end:WikiTextTocRule:13 --><!-- ws:start:WikiTextTocRule:14: --> | <a href="#The rank one case">The rank one case</a><!-- ws:end:WikiTextTocRule:14 --><!-- ws:start:WikiTextTocRule:15: --> | <a href="#Complete searches for temperaments">Complete searches for temperaments</a><!-- ws:end:WikiTextTocRule:15 --><!-- ws:start:WikiTextTocRule:16: --> | <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"><html><head><title>Recoverability</title></head><body><!-- ws:start:WikiTextTocRule:10:&lt;img id=&quot;wikitext@@toc@@flat&quot; class=&quot;WikiMedia WikiMediaTocFlat&quot; title=&quot;Table of Contents&quot; src=&quot;/site/embedthumbnail/toc/flat?w=100&amp;h=16&quot;/&gt; --><!-- ws:end:WikiTextTocRule:10 --><!-- ws:start:WikiTextTocRule:11: --><a href="#Definition">Definition</a><!-- ws:end:WikiTextTocRule:11 --><!-- ws:start:WikiTextTocRule:12: --> | <a href="#Segments">Segments</a><!-- ws:end:WikiTextTocRule:12 --><!-- ws:start:WikiTextTocRule:13: --> | <a href="#The recoverability norm">The recoverability norm</a><!-- ws:end:WikiTextTocRule:13 --><!-- ws:start:WikiTextTocRule:14: --> | <a href="#The rank one case">The rank one case</a><!-- ws:end:WikiTextTocRule:14 --><!-- ws:start:WikiTextTocRule:15: --> | <a href="#Complete searches for temperaments">Complete searches for temperaments</a><!-- ws:end:WikiTextTocRule:15 --><!-- ws:start:WikiTextTocRule:16: --> | ||
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<!-- ws:start:WikiTextHeadingRule:6:&lt;h1&gt; --><h1 id="toc3"><a name="The rank one case"></a><!-- ws:end:WikiTextHeadingRule:6 -->The rank one case</h1> | <!-- ws:start:WikiTextHeadingRule:6:&lt;h1&gt; --><h1 id="toc3"><a name="The rank one case"></a><!-- ws:end:WikiTextHeadingRule:6 -->The rank one case</h1> | ||
In the case of rank one, if W is an N-edo val, ie whose first coefficient is N. then W∨2 = N and (W∨2)∧J = NJ, so that rounding it gives the patent val for N. Hence, W is recoverable if and only if it is a patent val. However, ]W∧J[ &lt; 600 cents is now a stringent condition for p&gt;5, especially in higher prime limits. In the 5-limit we have 4, 5, 7, 8, 12, 15, 19, 22, 23, 26, 27, 31, 34 ... . The 7-limit grows somewhat restrictive: 19, 27, 31, 41, 49, 60, 68, 72, 80, 91, 99... . In the 11-limit we have 49, 72, 103, 239, 270, 342, 391, 414, 445, 494, 552, 612... . The 13-limit is already quite restrictive: 552, 954, 1133, 1236, 1506..., and the 17-limit starts off 4452, 5527, 7033, 7315, 9896... .<br /> | In the case of rank one, if W is an N-edo val, ie whose first coefficient is N. then W∨2 = N and (W∨2)∧J = NJ, so that rounding it gives the patent val for N. Hence, W is recoverable if and only if it is a patent val. However, ]W∧J[ &lt; 600 cents is now a stringent condition for p&gt;5, especially in higher prime limits. In the 5-limit we have 4, 5, 7, 8, 12, 15, 19, 22, 23, 26, 27, 31, 34 ... . The 7-limit grows somewhat restrictive: 19, 27, 31, 41, 49, 60, 68, 72, 80, 91, 99... . In the 11-limit we have 49, 72, 103, 239, 270, 342, 391, 414, 445, 494, 552, 612... . The 13-limit is already quite restrictive: 552, 954, 1133, 1236, 1506..., and the 17-limit starts off 4452, 5527, 7033, 7315, 9896... .<br /> | ||
<br /> | |||
If W is the patent val for N-edo and ]W∧J[ &gt; 600 cents, it can happen that the minimum value for recoverability relative error/simple badness, defined as ]V∧J[ for any N-edo val V, does not occur for V = W. Examples are 13-limit 12f, where ]12f∧J[ = 1217.949 is much smaller than ]12∧J[ = 3844.172, 5-limit 17c, ]17c∧J[ = 847.730 compared to ]17∧J[ = 1054.225, and 11-limit 27e, where ]27e∧J[ = 1169.472 is less than ]27∧J[ = 2405.855. Of course two possibilities can be close enough that both are plausible, as with 7-limit 34d at 1169.472 cents versus 34 at 1437.444 cents.<br /> | |||
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<!-- ws:start:WikiTextHeadingRule:8:&lt;h1&gt; --><h1 id="toc4"><a name="Complete searches for temperaments"></a><!-- ws:end:WikiTextHeadingRule:8 -->Complete searches for temperaments</h1> | <!-- ws:start:WikiTextHeadingRule:8:&lt;h1&gt; --><h1 id="toc4"><a name="Complete searches for temperaments"></a><!-- ws:end:WikiTextHeadingRule:8 -->Complete searches for temperaments</h1> | ||
By a complete search for regular temperaments is meant a search which is guaranteed to find all temperaments meeting certain specified conditions. Recoverability conditions provide one approach to these. The first segment of W∨2 consists of C(n-1, r-1) zeros, and the second segment of C(n-1, r) integers identical to the initial, 2 containing, segment of W. By beginning with such a multivector of integer coefficients, wedging with J, and rounding, we obtain a multivector which is a candidate for a p-limit rank r wedgie, defining a regular temperament. It will not in general be a wedgie, but all recoverable wedgies can be obtained in this way. Hence all that remains to do, as discussed in <a class="wiki_link" href="/The%20wedgie">The wedgie</a>, is to test if the multivector in question is actually a wedgie, and also if it passes any further conditions on complexity, error of badness we wish to place on our list of wedgies.</body></html></pre></div> | By a complete search for regular temperaments is meant a search which is guaranteed to find all temperaments meeting certain specified conditions. Recoverability conditions provide one approach to these. The first segment of W∨2 consists of C(n-1, r-1) zeros, and the second segment of C(n-1, r) integers identical to the initial, 2 containing, segment of W. By beginning with such a multivector of integer coefficients, wedging with J, and rounding, we obtain a multivector which is a candidate for a p-limit rank r wedgie, defining a regular temperament. It will not in general be a wedgie, but all recoverable wedgies can be obtained in this way. Hence all that remains to do, as discussed in <a class="wiki_link" href="/The%20wedgie">The wedgie</a>, is to test if the multivector in question is actually a wedgie, and also if it passes any further conditions on complexity, error of badness we wish to place on our list of wedgies.</body></html></pre></div> | ||