Talk:QR decomposition: Difference between revisions
→Draft status
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:: I did now. Thanks for your hints. Are there any other objections? --[[User:Avi|Avi]] 17:02, 12 July 2011 (UTC)
::: What is this line of make-householder doing? (beta (/ 2 (mmul (mtp v) v))))
:::: It creates a local variable <math>\beta</math> (which is often used in articles about the QR decomposition) with the value <math>\frac{2}{v^T v}</math>, and is used to create the Householder matrix <math>H = I - \beta \, v v^T</math>. I also could have written the first formula directly instead of that. --[[User:Avi|Avi]] 18:18, 13 July 2011 (UTC)
::::<lang lisp>(m- (eye m)
(.* (/ 2 (mmul (mtp v) v)))
(mmul v (mtp v))))</lang>
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