Tenney–Euclidean tuning: Difference between revisions

Wikispaces>genewardsmith
**Imported revision 163292193 - Original comment: **
Wikispaces>genewardsmith
**Imported revision 167505323 - Original comment: **
Line 1: Line 1:
<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>2010-09-16 19:09:31 UTC</tt>.<br>
: This revision was by author [[User:genewardsmith|genewardsmith]] and made on <tt>2010-10-04 04:25:49 UTC</tt>.<br>
: The original revision id was <tt>163292193</tt>.<br>
: The original revision id was <tt>167505323</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>
Line 12: Line 12:


===The pseudoinverse===
===The pseudoinverse===
If A is an mxn matrix with real entries, and if we denote the pseudoinverse by A`, then it is defined as the nxm matrix such that
If A is an m**x**n matrix with real entries, and if we denote the pseudoinverse by A`, then it is defined as the n**x**m matrix such that
# AA`A = A. Hence, AA` maps the rows of A to itself and A`A the columns of A to itself.
# AA`A = A. Hence, AA` maps the rows of A to itself and A`A the columns of A to itself.
# A`AA` = A
# A`AA` = A
Line 25: Line 25:
* A`A is the orthogonal projection map onto the space spanned by the rows of A
* A`A is the orthogonal projection map onto the space spanned by the rows of A
* I - A`A, where I is the identity matrix, is the orthogonal projection map onto the kernel, or null space, of A
* I - A`A, where I is the identity matrix, is the orthogonal projection map onto the kernel, or null space, of A
* If the rows of A are linearly independent, then A` = At(AAt)^(-1), where At is the transpose of A. This means the pseudoinverse can be found in this important special case by people who don't have a pseudoinverse routine available by using a matrix inverse routine.
* If the rows of A are linearly independent, then A` = A*(AA*)^(-1), where A* is the transpose of A. This means the pseudoinverse can be found in this important special case by people who don't have a pseudoinverse routine available by using a matrix inverse routine.
* uA` is the nearest point to u in the subspace spanned by the rows of A; A`v is the nearest point to v in the space spanned by the columns of A.
* uA` is the nearest point to u in the subspace spanned by the rows of A; A`v is the nearest point to v in the space spanned by the columns of A.


Line 47: Line 47:
&lt;br /&gt;
&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc1"&gt;&lt;a name="x-RMS tuning-The pseudoinverse"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt;The pseudoinverse&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:2:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc1"&gt;&lt;a name="x-RMS tuning-The pseudoinverse"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:2 --&gt;The pseudoinverse&lt;/h3&gt;
If A is an mxn matrix with real entries, and if we denote the pseudoinverse by A`, then it is defined as the nxm matrix such that&lt;br /&gt;
If A is an m&lt;strong&gt;x&lt;/strong&gt;n matrix with real entries, and if we denote the pseudoinverse by A`, then it is defined as the n&lt;strong&gt;x&lt;/strong&gt;m matrix such that&lt;br /&gt;
&lt;ol&gt;&lt;li&gt;AA`A = A. Hence, AA` maps the rows of A to itself and A`A the columns of A to itself.&lt;/li&gt;&lt;li&gt;A`AA` = A&lt;/li&gt;&lt;li&gt;A`A and AA` are symmetric matricies&lt;/li&gt;&lt;/ol&gt;&lt;br /&gt;
&lt;ol&gt;&lt;li&gt;AA`A = A. Hence, AA` maps the rows of A to itself and A`A the columns of A to itself.&lt;/li&gt;&lt;li&gt;A`AA` = A&lt;/li&gt;&lt;li&gt;A`A and AA` are symmetric matricies&lt;/li&gt;&lt;/ol&gt;&lt;br /&gt;
From these properties it can be deduced that&lt;br /&gt;
From these properties it can be deduced that&lt;br /&gt;
&lt;ul&gt;&lt;li&gt;If A is invertible, its inverse is A`&lt;/li&gt;&lt;li&gt;If A has rational entries, so does A`&lt;/li&gt;&lt;li&gt;A`` = A&lt;/li&gt;&lt;li&gt;The pseudoinverse of the transpose is the transpose of the pseudoinverse&lt;/li&gt;&lt;li&gt;AA` is the orthogonal projection map onto the space spanned by the columns of A&lt;/li&gt;&lt;li&gt;A`A is the orthogonal projection map onto the space spanned by the rows of A&lt;/li&gt;&lt;li&gt;I - A`A, where I is the identity matrix, is the orthogonal projection map onto the kernel, or null space, of A&lt;/li&gt;&lt;li&gt;If the rows of A are linearly independent, then A` = At(AAt)^(-1), where At is the transpose of A. This means the pseudoinverse can be found in this important special case by people who don't have a pseudoinverse routine available by using a matrix inverse routine.&lt;/li&gt;&lt;li&gt;uA` is the nearest point to u in the subspace spanned by the rows of A; A`v is the nearest point to v in the space spanned by the columns of A.&lt;/li&gt;&lt;/ul&gt;&lt;br /&gt;
&lt;ul&gt;&lt;li&gt;If A is invertible, its inverse is A`&lt;/li&gt;&lt;li&gt;If A has rational entries, so does A`&lt;/li&gt;&lt;li&gt;A`` = A&lt;/li&gt;&lt;li&gt;The pseudoinverse of the transpose is the transpose of the pseudoinverse&lt;/li&gt;&lt;li&gt;AA` is the orthogonal projection map onto the space spanned by the columns of A&lt;/li&gt;&lt;li&gt;A`A is the orthogonal projection map onto the space spanned by the rows of A&lt;/li&gt;&lt;li&gt;I - A`A, where I is the identity matrix, is the orthogonal projection map onto the kernel, or null space, of A&lt;/li&gt;&lt;li&gt;If the rows of A are linearly independent, then A` = A*(AA*)^(-1), where A* is the transpose of A. This means the pseudoinverse can be found in this important special case by people who don't have a pseudoinverse routine available by using a matrix inverse routine.&lt;/li&gt;&lt;li&gt;uA` is the nearest point to u in the subspace spanned by the rows of A; A`v is the nearest point to v in the space spanned by the columns of A.&lt;/li&gt;&lt;/ul&gt;&lt;br /&gt;
&lt;!-- ws:start:WikiTextHeadingRule:4:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc2"&gt;&lt;a name="x-RMS tuning-Computing the TOP-RMS tuning"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:4 --&gt;Computing the TOP-RMS tuning&lt;/h3&gt;
&lt;!-- ws:start:WikiTextHeadingRule:4:&amp;lt;h3&amp;gt; --&gt;&lt;h3 id="toc2"&gt;&lt;a name="x-RMS tuning-Computing the TOP-RMS tuning"&gt;&lt;/a&gt;&lt;!-- ws:end:WikiTextHeadingRule:4 --&gt;Computing the TOP-RMS tuning&lt;/h3&gt;
Suppose V is a matrix whose rows consist of vals in the weighted basis. No assumption need be made that the rows are linearly independent or that common factors (&amp;quot;torsion problems&amp;quot;) cannot be found in some combination of the unweighted vals. If J is the JI point, &amp;lt;1 1 ... 1|, then JV` gives the TOP-RMS tuning in the sense that it gives (not necessarily independent) generators which correspond to the rows of V. How many of each generator to take to map a rational number contained in the prime limit in question is determined by applying the val corresponding to the generator to the rational number.&lt;br /&gt;
Suppose V is a matrix whose rows consist of vals in the weighted basis. No assumption need be made that the rows are linearly independent or that common factors (&amp;quot;torsion problems&amp;quot;) cannot be found in some combination of the unweighted vals. If J is the JI point, &amp;lt;1 1 ... 1|, then JV` gives the TOP-RMS tuning in the sense that it gives (not necessarily independent) generators which correspond to the rows of V. How many of each generator to take to map a rational number contained in the prime limit in question is determined by applying the val corresponding to the generator to the rational number.&lt;br /&gt;