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=== SPACE GROUP EXERCISE PROGRAM SPGR  (30/3/98) ===
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SPGR is a small application that uses the symmetry handler that
is also part of PLUTON and PLATON. This program allows for easy
access to space group related data and operations in interactive 
mode

The program may be compiled as: f77 -o spgr spgr.f

The console output for a sample run

spgr P41212 

is given hereafter.

SAMPLE OUTPUT:
==============

=== SPACE GROUP EXERCISE PROGRAM ===
 ----------------------------------------

TYPE <HELP> FOR HELP OR INSTRUCTION

Space Group P41212                 No:  92, Laue:4/mmm [Hall:  P 4abw 2nw      ]

Lattice Type tP, Acentric,   Tetragonal, Order   8( 8) [Shoenflies: D4^4       ]

CHIRAL  - See P.G. Jones, Acta Cryst. (1986), A42, 57.

  Nr            ***** Symmetry Operation(s) *****

   1               X ,              Y ,              Z               
   2         1/2 - Y ,        1/2 + X ,        1/4 + Z               
   3             - X ,            - Y ,        1/2 + Z               
   4         1/2 + Y ,        1/2 - X ,        3/4 + Z               
   5         1/2 + X ,        1/2 - Y ,        3/4 - Z               
   6               Y ,              X ,            - Z               
   7         1/2 - X ,        1/2 + Y ,        1/4 - Z               
   8             - Y ,            - X ,        1/2 - Z               


END SAMPLE Output
=================

The program can be invoked also with 

spgr

so that instructions can be given at the prompt >>


Symmetry may be specified with instructions such as 

SPGR P41

or 

LATT P C
SYMM -x,1/2+y,0.5-Z

etc.

The Results can be listed with

LIST


The effect of symmetry on coordinates may be listed with e.g.

ATOM .1111 .2222 .3333

Similar instructions for the reciprocal lattice are:

RLST

and

HKL 1 2 3


Other options may be gleaned from the

HELP

instruction