Generator preimage: Difference between revisions
Wikispaces>genewardsmith **Imported revision 238731837 - Original comment: ** |
Wikispaces>genewardsmith **Imported revision 238732299 - 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>2011-06-25 16: | : This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2011-06-25 16:44:54 UTC</tt>.<br> | ||
: The original revision id was <tt> | : The original revision id was <tt>238732299</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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* Take the transpose of the pseudoinverse of V, call that U | * Take the transpose of the pseudoinverse of V, call that U | ||
* Find a basis for the commas of V | * Find a basis for the commas of V | ||
* For each row of U, clear denominators and append the monzos of the comma basis for V | * For each row U[i] of U, clear denominators and append the monzos of the comma basis for V | ||
* Saturate the result to a list of monzos, call that S | * Saturate the result to a list of monzos, call that S | ||
* Apply | * Apply the ith val V[i] (dot product) to each element of S | ||
* Insert V.S[ | * Insert V[i].S[j] in front of the elements of S[j] as the first element, obtaining a modified list T | ||
* Hermite reduce the modified list T, take the first row, and remove the first element (which should be a 1.) | * Hermite reduce the modified list T, take the first row, and remove the first element (which should be a 1.) | ||
* Consider the rest to be a monzo, which may be converted to a rational number if you prefer | * Consider the rest to be a monzo, which may be converted to a rational number if you prefer | ||
* This is the corresponding transveral generator to the ith val of V; it may be reduced to an equivalent generator of minimal Tenney height by multiplying by the commas of V | * This is the corresponding transveral generator to the ith val V[i] of V; it may be reduced to an equivalent generator of minimal Tenney height by multiplying by the commas of V | ||
</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>Transversal generators</title></head><body><!-- ws:start:WikiTextTocRule:6:&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:6 --><!-- ws:start:WikiTextTocRule:7: --><a href="#Definition">Definition</a><!-- ws:end:WikiTextTocRule:7 --><!-- ws:start:WikiTextTocRule:8: --> | <a href="#Examples">Examples</a><!-- ws:end:WikiTextTocRule:8 --><!-- ws:start:WikiTextTocRule:9: --> | <a href="#Finding the transversal generators">Finding the transversal generators</a><!-- ws:end:WikiTextTocRule:9 --><!-- ws:start:WikiTextTocRule:10: --> | <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>Transversal generators</title></head><body><!-- ws:start:WikiTextTocRule:6:&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:6 --><!-- ws:start:WikiTextTocRule:7: --><a href="#Definition">Definition</a><!-- ws:end:WikiTextTocRule:7 --><!-- ws:start:WikiTextTocRule:8: --> | <a href="#Examples">Examples</a><!-- ws:end:WikiTextTocRule:8 --><!-- ws:start:WikiTextTocRule:9: --> | <a href="#Finding the transversal generators">Finding the transversal generators</a><!-- ws:end:WikiTextTocRule:9 --><!-- ws:start:WikiTextTocRule:10: --> | ||
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We can find transveral generators for V by the following procedure:<br /> | We can find transveral generators for V by the following procedure:<br /> | ||
<br /> | <br /> | ||
<ul><li>Take the transpose of the pseudoinverse of V, call that U</li><li>Find a basis for the commas of V</li><li>For each row of U, clear denominators and append the monzos of the comma basis for V</li><li>Saturate the result to a list of monzos, call that S</li><li>Apply | <ul><li>Take the transpose of the pseudoinverse of V, call that U</li><li>Find a basis for the commas of V</li><li>For each row U[i] of U, clear denominators and append the monzos of the comma basis for V</li><li>Saturate the result to a list of monzos, call that S</li><li>Apply the ith val V[i] (dot product) to each element of S</li><li>Insert V[i].S[j] in front of the elements of S[j] as the first element, obtaining a modified list T</li><li>Hermite reduce the modified list T, take the first row, and remove the first element (which should be a 1.)</li><li>Consider the rest to be a monzo, which may be converted to a rational number if you prefer</li><li>This is the corresponding transveral generator to the ith val V[i] of V; it may be reduced to an equivalent generator of minimal Tenney height by multiplying by the commas of V</li></ul></body></html></pre></div> | ||