[hchen]

Hi All:

I have a question about the local coordinate set up. Say I want to set up a local Cartesian coordinate based on two unit vectors: e1 as local x and e2 as local y. The third one should be determined by right hand rule.

Should it be something like:

        const coordinateSystem localCS_
              (
                  "localCS",
                  vector(0,0,0),
                  e1,
                  e2
              );

I can not understand the constructors of a coordinate system. It seems that they need a axis and a direction, but what is the direction of a coordinate system?

Best regards
Hao

[jhoepken]

The constructor needs a name and an origin, both should be fairly straight forward to understand. However, the next two vectors are e1 and e3, which are used to compute e2. I don't get what you mean by "direction" of a coordinate system.

[hchen]

Hi Jens:

I mean that should it be:

        const coordinateSystem localCS_
              (
                  "localCS",
                  vector(0,0,0),
                  e1,
                  e3
              );

or

        const coordinateSystem localCS_
              (
                  "localCS",
                  vector(0,0,0),
                  e3,
                  e1
              );