Re: [eigen] Using transpose in expressions

[Christoph Hertzberg <chtz@xxxxxxxxxxxxxxxxxxxxxxxx>]

I can confirm this, also on 3.2.8 and 3.2-head. It does work on the 3.3 
branch, however (which has a significantly different evaluator structure).

I don't know how to best fix this (I'm not _that_ familiar with Eigen's 
internals).
Meanwhile, you can work-around this by by adding an .eval() before or 
after the .transpose()

Christoph

On 2016-03-26 13:51, Brad Bell wrote:
> Why does the following program  work when ERROR_CASE is zero and
> generates a compile error when ERROR_CASE is one
> (I am using eigen-3.2.7).
>
> # include <iostream>
> # include <Eigen/Core>
> # define ERROR_CASE 1
> int main(void)
> {   typedef Eigen::Matrix<double, Eigen::Dynamic, Eigen::Dynamic> matrix;
>      //
>      matrix A = matrix::Identity(2, 2);
> # if ERROR_CASE
>      matrix C = A * (A * A).transpose();
> # else
>      matrix C = A * A * A.transpose();
> # endif
>      //
>      std::cout << "C = \n" << C << "\n";
> }

--
 Dipl. Inf., Dipl. Math. Christoph Hertzberg

 Universität Bremen
 FB 3 - Mathematik und Informatik
 AG Robotik
 Robert-Hooke-Straße 1
 28359 Bremen, Germany

 Zentrale: +49 421 178 45-6611

 Besuchsadresse der Nebengeschäftsstelle:
 Robert-Hooke-Straße 5
 28359 Bremen, Germany

 Tel.:    +49 421 178 45-4021
 Empfang: +49 421 178 45-6600
 Fax:     +49 421 178 45-4150
 E-Mail:  chtz@xxxxxxxxxxxxxxxxxxxxxxxx

 Weitere Informationen: http://www.informatik.uni-bremen.de/robotik