performance - dgemm or dgemv for Matrix Multiplication? -

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i know dgemv matrix-vector, more efficient? using dgemm directly matrix multiplication or using dgemv matrix multiplication multiplying matrix each individual column of matrix b using dgemv?

if make repeated calls dgemv, not benefit cache tiling , re-use, biggest advantages dgemm implementations have. dgemm vastly more efficient multiple calls dgemv.


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