I'm searching for the mathematical name and notation of a special case of the element-wise multiplication .* in Matlab shown in the following picture:
I'm aware that this would be called Hadamard- or Schur-product for the case of equal dimensions but how can this operation be denoted for cases like the given one?
Thanks.
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$\begingroup$I've never seen a standard notation for this, but you could easily define one. Let $f: \mathbb{R}^2 \to M_{2\times 2}$ send $(\alpha, \beta)$ to the diagonal matrix with those entries. Then your operation is$$A \,.^*\, v = f(v)A.$$
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