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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] TopicCustomizingEigen
- From: Gael Guennebaud <gael.guennebaud@xxxxxxxxx>
- Date: Thu, 19 May 2011 09:31:04 +0200
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oops, indeed, this page is completely out of date :( The new way to
support custom types is to specialize XXX_impl structures, where XXX
is, e.g., sqrt, abs, real, etc.
Regarding nested, if your scalar type is heavy, you can use a reference, e.g.:
typedef T & Nested;
to reduce copies.
cheers,
gael
On Thu, May 19, 2011 at 12:47 AM, Bob Carpenter <carp@xxxxxxxxxxx> wrote:
> As I was extending Eigen for automatic differentiation,
> I was led to NumTraits through error messages and eventually
> found your customizing Eigen topic:
>
> http://eigen.tuxfamily.org/api/TopicCustomizingEigen.html
>
> The example looks to be a bit out of date, as the
> NumTraits example is missing the two enums:
>
> RequireInitization
> HasFloatingPoint
>
> and doesn't mention the four methods I implemented,
> epsilon(), dummy_precision(), highest(), and lowest().
>
> I'm also not sure I'm using the Nested typedef properly -- I
> just followed your instructions in the doxygen doc to set it
> to the same as the template variable T.
>
> The doxygen page for NumTraits:
>
> http://eigen.tuxfamily.org/dox/structEigen_1_1NumTraits.html
>
> is missing the "generated from the following file", which is odd,
> as NumTraits.h is where I expected to find it.
>
> - Bob Carpenter
> Columbia Uni, Dept. of Statistics
>
>
>