Re: [eigen] Specializing max_coeff_visitor for some number types |

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On Mon, 7 Apr 2014, Marc Glisse wrote:

`As you can see in LU, there is a subtlety I hadn't thought of: max(abs) was
``returning a RealScalar, not a Scalar. That's not a big problem when we only
``want to compare it with 0.
`

`Note that we end up computing twice as many abs() as before, because we
``store the coefficient in the visitor and not the result of abs. Avoiding
``it would be possible, adding a new unary functor that defaults to
``scalar_abs_op, storing its result_type in the visitor, calling it before
``passing the result to better_coeff_op, and making better_coeff_op work on
``this new type. But that's starting to get a bit complicated for such a
``simple feature...
`
--
Marc Glisse