DATE     94/01/10

    Opérateur ANTI :                           See also :SYMT BLOQ 
    --------------                                       RELA RESO 
                                                         REAC TRAC 


   RIG1 = ANTI ('DEPL') ('ROTA') POIN1 POIN2 (POIN3 si 3D) GEO1 (FLOT1)

    Description :
    _____________

    The ANTISYMETRIE operator enables the user to impose boundary
 conditions of antisymmetrical type on the d.o.f. in DEPLACEMENT
 and/or ROTATION :
 

    Contents :
    __________

    This operator creates the RIG1 object of RIGIDITE type
 associated with the boundary conditions. It will have to
 be added to the stiffness of the calculated structure.



    POIN1,POIN2       : points defining the AXE of ANTISYMETRIE
                        in 2D (POINT type)

    POIN1,POIN2,POIN3 : points defining the PLAN of ANTISYMETRIE
                        in 3D (POINT type)

    GEO1              : object on which the boundary conditions are
                        imposed (MAILLAGE type)

    FLOT1             : value of the criterion for selecting the
                        points belonging to the axis/plane of
                        antisymmetry (FLOTTANT type)
                        By default, 1/10th of the current density
                        is used.
                        FLOT1 is therefore REQUIRED when no density
                        has been defined before
                        
    'DEPL'            : key word for creating boundary conditions 
                        of ANTISYMETRIE type on the displacememt 
                        d.o.f.

    'ROTA'            : key word for creating boundary conditions
                        of ANTISYMETRIE type on the rotation 
                        d.o.f.

 At least one of these two aforementioned specifications is
 COMPULSORY.


    CAUTION  The selection of the criterion conditions the entire  
    _______  set of points on which the conditions of antisymmetry 
             will apply. It is advisable to choose carefully on
             the one hand, and to display the generated restraints 
             by means of the TRAC operator on the other.