On 4/12/2013 8:48 AM, Kent A. Reed wrote: > On 4/12/2013 8:22 AM, andy pugh wrote: >> Someone on the forum seems to have spotted something odd in >> pmMatRpyConvert >> http://www.linuxcnc.org/index.php/english/forum/30-cnc-machines/26392-the-study-of-arithmetic#32609 >> >> >> At best it seems like there is redundant code. >> > > Don't have my fingers on the right reference (yet) and my brain is > rusty but I expect the seemingly odd coding is protection against the > usual problems representing mathematical functions in binary > arithmetic. Don't be too quick to suspect redundant code. Then again, > trust but verify! > > If I get a chance later today I'll look for something I can pass to > these guys on the forum. > >
I shouldn't compose email while sitting "on hold" with a medical insurance representative. Too distracting. At a glance, the form of the code looked ok but now that I've actually read it, I agree with the OP that comparing the computed value of pitch with +/-2*pi doesn't make sense (that's two revolutions of a wrist!?!). It's not that the clauses triggered by the if tests are redundant code, it's that they can never be executed because of a coding mistake. Fortunately, it may not matter in most usage, but it's annoying. My first inclination is to say someone meant PM_PI_2 instead of 2 * PM_PI but I don't want to shoot from the hip again. Needs some investigation. Unfortunately, the posemath routines come from early in the development of the Realtime Control System (RCS) and are essentially undocumented:-( Has anyone actually exercised the rountines related to roll-pitch-yaw (Rpy), especially the mappings to/from rotation matrices? Regards, Kent ------------------------------------------------------------------------------ Precog is a next-generation analytics platform capable of advanced analytics on semi-structured data. The platform includes APIs for building apps and a phenomenal toolset for data science. Developers can use our toolset for easy data analysis & visualization. Get a free account! http://www2.precog.com/precogplatform/slashdotnewsletter _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
