2.32                      ********************
                                  * O_TO_SP WRITE-UP *
                                  ********************


          Interactive program, to extract from a 3D transformation
        matrix and translation vector, the corresponding spherical polar
        angles, axis location and post rotation translation along the
        axis direction. Thus, for example, one can obtain an estimate
        of the transformation operator via the "O" program, use this
        program to convert the NC symmetry operator information to PHASES
        format, and use the PHASES routines for operator refinement
        averaging, skewing etc. The user is prompted for the elements of the
        transformation matrix and vector, which can be found in the
        appropriate O data block.  Note that the program is not limited
        to transformations from "O". As long as the input transformation
        operation was to be applied to orthogonal coordinates which are
        orthogonalized as in the PDB, then the output will be valid.