Hello!

Iam totally new to Eigen. Currently iam writing my bachelor thesis in Electronical Engeneering and i had to use Eigen
I just want to create a Transform object containing translate, scale and rotate and apply it to a point.
After reading some stuff in the documentation i came to this:

# include <i o s t r e a m >
# include <Eigen / Dense>
using namespace Eigen ;
int main ( )
{
Vector3f P1 , P2 , t , s , r_axis ;
P1 << 1 , 0 , 0 ;
t << 2 , 2 , 2 ; // translation vector
s << 2 , 2 , 2 ; // scale vector
r_axis << 1 , 0 , 0 ; // rotate around this axis -> x
Transform<float , 3 , Affine> M = Translation3f ( t ) ∗ AngleAxisf ( 0 . 5 2 , r_axis ) ∗ Scaling ( s ) ;
P2 = M ∗ P1 ;
return 0 ;
}

this gets me a big wall of errors i dont understand well.
my problem is i have got only 2 days left before the end of my thesis, so i havent got the time to crawl through all the documentation.

For the record, you have to split that line (c++ issue):

Code: Select all

Transform<float , 3 , Affine> M;
M = Translation3f ( t ) ∗ AngleAxisf ( 0 . 5 2 , r_axis ) ∗ Scaling ( s ) ;


Hi, thanks!

ich changed it to this:

#include <iostream>
#include "Eigen/Dense"

using namespace Eigen;

int main ( )
{
Vector3f P1 , P2 , t , s , r_axis ;

P1 << 1, 0, 0;
t << 2, 2, 2; // Translationsvektor
s << 2, 2, 2; // Skalierung
r_axis << 1, 0, 0; // Um die Achse wird gedreht

Transform<float,3,Affine> M;
M.translate(t);

//P2 = M ∗ P1 ;

return 0 ;
}


this actually works but if i uncomment the line P2 = .. than it doesnt work

i dont know why..

greetings.

what's wrong? it works for me.

even if you uncomment "//P2 = M * P1" -> "P2 = M * P1"?!

My only Problem is i cant apply the Transformation to a point!

greetings Benni

yes. Please post your errors, how can we help without them?

Hi,

yes i know. the problem is its on german. i dont know how to switch the language of the compilermessages.
Maybe you compile the code on your own?

i appreciate your help! thanks so far.

Benni

When I copied-and-pasted your program, I found that the asterisk in the line

Code: Select all

P2 = M ∗ P1 ;


is not the normal asterisk denoting multiplication, but another character (compare normal * with your ∗ ). I don't know how this happened, but that might be your problem. Apart from that, the program works fine.

If this does not solve it, give us the error message in German (perhaps with your translation) and the version of Eigen and the compiler that you are using.

Hello,

yes the asterisk was not rigth. I have absolutely no clue how this happend. Took me hours trying to solve my "Eigen problem".
Thank you very much sir.

greetings