Douglas Blumeyer's RTT How-To: Difference between revisions

Cmloegcmluin (talk | contribs)
vectors and covectors: warning about ephemerality
Cmloegcmluin (talk | contribs)
multimaps: Cloud not Alpha
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So just set these inside a number brackets equal to the rank, and we’ve got {{multicovector|1 4 4}}.
So just set these inside a number brackets equal to the rank, and we’ve got {{multicovector|1 4 4}}.


Wolfram Alpha won't be able to put the answer in brackets for you, but it can calculate the list of minors at least. The only trick is that you have to tell it the rank of your matrix as the second argument:
Wolfram Language doesn't have a built in way to show the proper count of brackets, but its Minors function can at least calculate the list of minors for you. The only trick is that you have to tell it the rank of your matrix as the second argument:


{| class="wikitable"
{| class="wikitable"
|+WolframAlpha code ([https://www.wolframalpha.com/input/?i=Minors%5B%7B%7B1%2C0%2C-4%7D%2C%7B0%2C1%2C4%7D%7D%2C+2%5D try it])
!input
!input
!output
!output
|-
|-
|<code>Minors[{{1,0,-4},{0,1,4}}, 2]</code>
|<code>wedge[m_] := Minors[m, Length[m]]</code>
|<nowiki>{{1, 4, 4}}</nowiki>
 
<code>wedge[{{1,0,-4},{0,1,4}}]</code>
|<nowiki>{1, 4, 4}</nowiki>
|}
|}


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{| class="wikitable"
{| class="wikitable"
|+WolframAlpha code ([https://www.wolframalpha.com/input/?i=Minors%5B%7B%7B12%2C19%2C28%7D%7D%2C+1%5D try it])
!input
!input
!output
!output
|-
|-
|<code>Minors[<nowiki>{{12,19,28}}</nowiki>, 1]</code>
|<code>wedge[<nowiki>{{12,19,28}}</nowiki>]</code>
|<nowiki>{{12, 19, 28}}</nowiki>
|<nowiki>{12, 19, 28}</nowiki>
|}
|}


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{| class="wikitable"
{| class="wikitable"
|+WolframAlpha code ([https://www.wolframalpha.com/input/?i=Minors%5B%7B%7B1%2C0%2C1%2C4%7D%2C%7B0%2C1%2C1%2C-1%7D%2C%7B0%2C0%2C-2%2C3%7D%7D%2C+3%5D try it])
!input
!input
!output
!output
|-
|-
|<code>Minors[{{1,0,1,4},{0,1,1,-1},{0,0,-2,3}}, 3]</code>
|<code>wedge[{{1,0,1,4},{0,1,1,-1},{0,0,-2,3}}]</code>
|<nowiki>{{-2, 3, 1, -11}}</nowiki>
|<nowiki>{-2, 3, 1, -11}</nowiki>
|}
|}