On May 11, 2007, at 2:09 PM, Bob Hanson wrote: >> original >> ATOM 1 ATOM 2 d(2-1) M*d >> x 3.95 3.86 -0.08 -1.25 >> y 38.05 36.58 -1.48 0.59 >> z 17.44 17.32 -0.11 0.53 >> >> >> transformed >> ATOM 1 ATOM 2 d(2-1) >> x 52.94 51.69 -1.25 >> y 50.01 50.6 0.59 >> z 89.41 89.95 0.53 >> >> >> that's good, but now I'm stuck. unapplying the translation does not >> get me to the transformed coords. this makes me think that... >> >> > Since M*(a2-a1) = (a2'-a1'), you simply add ATOM 1 coordinates now to > that and get the transformed coordinates. > > That is, calling A an initial coordinate, A' its transformed > coordinate, > A0 the coordinate (3.95, 38.05, 17.44) and A0' (52.94, 50.01, 89.41), > you have: > > A' = A0' + M*(A - A0) > > I think it probably doesn't matter what you use for A0'. > > Maybe I've lost the purpose of doing all this.... >
ack, but I won't know A0' when I do this for real. I'm trying to get from the original coords and the matrix, to the transformed coordinates. (in this particular case, I do know the transformed coordinates, but only because I'm trying to work out the equations. normally I will not know them in advance.) tim -- Timothy Driscoll em: [EMAIL PROTECTED] Virginia Bioinformatics Institute ph: 540-231-3007 Bioinformatics I: M-1 im: molvisions Washington St., Blacksburg, VA 24061 04-16-07. We will not forget you. ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Jmol-users mailing list Jmol-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jmol-users
