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EricDarve / numerical_linear_algebra

Julia code for the book Numerical Linear Algebra
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Eckart-Young #166

Closed shaundatta closed 4 years ago

shaundatta commented 4 years ago

The final clause of Theorem 5.4, "and moreover B minimizes || A-B ||," ought to include the stipulation "over rank-r matrices." For example, it could read "and moreover C=B minimizes || A-C ||_{2} over rank-r matrices C." As currently stated, one might interpret the minimum to be over all matrices in C^{mxn}, in which case B is not the minimizer.

EricDarve commented 4 years ago

Yes. You are right. Poorly stated.