Timeline for How to efficiently compute the generalized cross product?
Current License: CC BY-SA 4.0
12 events
| when toggle format | what | by | license | comment | |
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| Oct 3, 2018 at 21:41 | answer | added | Ben Mares | timeline score: 1 | |
| S Oct 3, 2018 at 20:45 | history | suggested | Alex Kritchevsky | CC BY-SA 4.0 |
Fixing TeX formatting
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| Oct 3, 2018 at 18:17 | review | Suggested edits | |||
| S Oct 3, 2018 at 20:45 | |||||
| Oct 22, 2012 at 8:21 | history | edited | aegirxx | CC BY-SA 3.0 |
added 194 characters in body
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| Oct 19, 2012 at 17:01 | vote | accept | aegirxx | ||
| Oct 19, 2012 at 1:08 | comment | added | Francois Monard | The last row is indeed weird because it enforces $x_n = \pm 1$, which cannot be possible if, say, you pick $\vec v_1 = \vec e_2$, ... $\vec v_{n-1} = \vec e_n$, in which case the only nonzero component of $x$ is the first one. There has to be a way of enforcing the right-hand rule, i.e. $\det (\vec v_1,...,\vec v_{n-1}, \vec v_1\times ...\times \vec v_{n-1}) \ge 0$, which is indeed the missing constraint. However, writing this condition as I just wrote it would amount to computing the components of the cross-product by determinants ! | |
| Oct 18, 2012 at 9:29 | answer | added | Federico Poloni | timeline score: 3 | |
| Oct 18, 2012 at 8:54 | history | edited | aegirxx | CC BY-SA 3.0 |
added 6 characters in body
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| Oct 17, 2012 at 22:25 | comment | added | Rabee Tourky | In many places in qhull determinants are not calculated just their signs. That speeds up hyperplane arrangement related algorithms. Can you tell me please where the particular code you need decoding in qhull is? | |
| Oct 17, 2012 at 21:45 | history | edited | aegirxx | CC BY-SA 3.0 |
changed "last row" to "last column" at cofactor expansion
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| Oct 17, 2012 at 21:20 | comment | added | Andreas Blass | The last row seems to be a step toward enforcing the $n$-dimensional analog of the familiar "right-hand rule" for 3 dimensions. | |
| Oct 17, 2012 at 20:35 | history | asked | aegirxx | CC BY-SA 3.0 |