Question #687331 on Yade changed: https://answers.launchpad.net/yade/+question/687331
Jan Stránský proposed the following answer: Hello, (apart from what Jerome already wrote) 1) x,y,z,w can be any number in general. x**2+y**2+z**2+w**2=1 hold for **unit** quaternions (which Yade uses) > is the w component a radians or a real number? is there a difference? w is internally a real number, you can access the internals as a.state.ori[0], a.state.ori[1], a.state.ori[2], a.state.ori [3] (have a look on Eigen / minieigen documentation which index correspond to x,y,z,w, I think (but I am not sure and don't want to search it right now) that the order is not x,y,z,w > a.state.orientation=... a.state.ori is the attribute (not orientation) > a.state.orientation=(10,10,10,10),how will the code responds? the easiest way is to try yourself :-) a.state.ori=(10,10,10,10) # error, as Jerome pointed a.state.ori = (10,10,10),10 # ok, 1st argument is axis, 2nd is angle print(a.state.ori) # you get axis-angle representation, not x,y,z,w directly, see above cheers Jan -- You received this question notification because your team yade-users is an answer contact for Yade. _______________________________________________ Mailing list: https://launchpad.net/~yade-users Post to : [email protected] Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
