The figures 4 and 5 in Chapter 11 BMC also help to visualize the difference
http://www.ruppweb.org/garland/gallery/Ch11/pages/Biomolecular_Crystallography_Fig_11-04_PART2.htm http://www.ruppweb.org/garland/gallery/Ch11/pages/Biomolecular_Crystallography_Fig_11-05.htm Best, BR -----Original Message----- From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Phil Evans Sent: Donnerstag, 27. März 2014 11:11 To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] difference between polar angle and eulerian angle The polar angles ?, ? define the direction of an axis about which a rotation by angle ? occurs, i.e. a single rotation around a defined axis. This is different from Eulerian angles which define 3 successive rotations around principal axes On 27 Mar 2014, at 06:11, Qixu Cai <caiq...@gmail.com> wrote: > Dear all, > > From the definition of CCP4 > (http://www.ccp4.ac.uk/html/rotationmatrices.html), the polar angle (?, ?, ?) > can be visualised as rotation ? about Z, rotation ? about the new Y, rotation > ? about the new Z. It seems the same as the ZXZ convention of eulerian angle > definition. What's the difference between the CCP4 polar angle definition and > eulerian angle ZXZ definition? > > And what's the definition of polar angle XYK convention in GLRF program? > > Thank you very much! > > Best wishes, > > -- > Qixu Cai > Email: caiq...@gmail.com > School of Life Sciences, > Xiamen University, Fujian, China > **from thunderbird**