Manual pages | Cast3M

$$$$ GIBI     NOTICE  CHAT      11/09/12    21:16:23     7124           
                                             DATE     11/09/12


             CASTEM2000 sytem  -  GIBI program
             ---------------------------------

 The GIBI program is based on the concept of OBJECT. An object
 stands for an abstract data structure used in scientific
 calculation methods, in particular in the finite elements method.
 
 The user can create an object by calling on an OPERATOR such as 
 "DROIT" or "TRAN".

 INSTRUCTIONS (DIRECTIVES) enable him to specify general 
 computation options or to perfom various actions. The "OPTION"
 instruction, for instance, is used to specify the space
 dimension and the type of element that the user wishes to create;
 the "DENSITE" instruction is used to define the mesh size
 the extremity of which will be a point created by this density. 

 Objects are known by their name (in the same way as operators)
 and type.
 
 The types of objects useful for creating a mesh in addition to words
 and numbers are :
 
          the POINT or mesh node.
          the MAILLAGE which stands for a mesh or a submesh
          and which, under its most general shape can be defined
          as being an element of P(P(E))
          

 The name of an object is allocated by means of the sign " = ".

 In order to create the whole object whose name is "UN" and value
 is 1, enter the following line :

          UN    =    1    ;

 The basic instruction of GIBI is as follows :

           result = operation (list of objects)

example:

  ARC    =   POIN1      CERCLE      CENTRE     POIN2       ;

 name of      name of   operator    name of    name of    ends
 generated    first     for         point at   second     the
 object       extremity creating    centre     extremity  GIBI
              point     an arc of   of         point    instruction 
                        a circle    arc 
                                                       

 There is an exception to this rule: there is no need of any operator
 to create a point :
               POINT=10. 0. 0. ;

 The format of the data of GIBI is free. Each instruction, which
 must not exceed seven cards ends with a semicolon.

 The cards with an * in first column are not taken into account;
 as a result they may enable the user to seize data comments.

 The names of operators and instuctions are characterized by their
 first four characters. The names of objects and key words are
 characterized by their first eight characters.
 
 There are three possibilities to lighten GIBI data :

 - The succession of operations : the result of an operation is 
             considered the first operand of the next operation
     example:
                     RESU = A ET B ET C ET D ;

 - Parentheses : the set of parentheses with their contents
                 is considered to be the generated object
     example:
                     SURFACE = LIGNE TRANSLATION ( P1 MOINS P2 );

 - The order of the different types of objects in an instruction 
                   is not important
     example:
                     TRAC OEIL GEOM; GEOM TRAC OEIL; OEIL TRAC GEOM;
     are the same operations.