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Timeline for vector to diagonal matrix [closed]

Current License: CC BY-SA 3.0

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Apr 24, 2016 at 12:28 history edited Stefan Kohl
Added top-level tag (bump the question -- maybe someone wishes to cast the remaining delete vote).
S Apr 24, 2015 at 16:33 history suggested isarandi CC BY-SA 3.0
This question indeed make sense.
Apr 24, 2015 at 16:11 review Suggested edits
S Apr 24, 2015 at 16:33
Feb 18, 2011 at 8:07 history closed Theo Johnson-Freyd
Yemon Choi
Denis Serre
David Roberts
Andrew Stacey
not a real question
Feb 18, 2011 at 7:25 answer added Tom De Medts timeline score: 16
Feb 18, 2011 at 6:43 comment added Yemon Choi Jerry, if I can't call it a method I am certainly not going to call it a notation. A notation cannot transform anything to anything. I find it hard to intuit what your actual question is
Feb 18, 2011 at 5:14 comment added Theo Johnson-Freyd I think this question should be improved before it is appropriate for MO. As is, I have voted to close, but I hope that instead OP rewrites it to clarify (you can modify the question by clicking the little "edit" button). Please see mathoverflow.net/howtoask .
Feb 18, 2011 at 4:34 comment added Anadim notation-wise that's $diag({\bf x})$. proof-wise, however, I agree with the first comment, you jump from a $1$-dimensional space to an $n$-dimensional space, so no linear operator can get you there. From the diagonal you can definitely go to the vector. Just multiply it with the all ones vector.
Feb 18, 2011 at 4:22 comment added Jerry Well you can hardly call it a method, it doesn't really do any multiplications, its basically just writing it in a way that implies its shape.
Feb 18, 2011 at 4:17 comment added Yemon Choi When you say "notation", do you mean "method"?
Feb 18, 2011 at 4:11 comment added Allen Knutson I have worried about this, and think the answer is basically no, largely because a column vector is rank 1 and the diagonal matrix is larger rank. But I wouldn't say that's a proof.
Feb 18, 2011 at 4:00 history asked Jerry CC BY-SA 2.5