Is there a simple notation to transform a column vector to a diagonal matrix with only matrix operations?
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closed as not a real question by Theo JohnsonFreyd, Yemon Choi, Denis Serre, David Roberts, Loop Space Feb 18 '11 at 8:07It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center. If this question can be reworded to fit the rules in the help center, please edit the question. 


I'm not sure whether it answers your question, but here is a "matrix procedure" to transform the column vector $v$ into a diagonal matrix $D$: Let $E_i$ be the $n \times n$ matrix with a $1$ on position $(i,i)$ and zeros everywhere else; similarly, let $e_i$ be the $1 \times n$ row matrix with a $1$ on position $(1,i)$ and zeros everywhere else. Then $$D = \sum_{i=1}^n E_i v e_i .$$ 

