DATE     95/08/18

    Opérateur ATG                              See also :COS 
    -------------                                        SIN 

    RESU1 = ATG  OBJET1  OBJET2 ;

    Description :
    _____________

    The ATG operator (arctangent) calculates the arctangent
 of OBJET1 / OBJET2. The result is expressed in degrees.

    Possible operations  :
    _____________________


----------------------------------------------------------------
|       OBJET1      |       OBJET2        |      RESU1         |
----------------------------------------------------------------
|       ENTIER      |       ENTIER        |      FLOTTANT      |
|       ENTIER      |      FLOTTANT       |      FLOTTANT      |
|      FLOTTANT     |       ENTIER        |      FLOTTANT      |
|      FLOTTANT     |      FLOTTANT       |      FLOTTANT      |
|      CHPOINT      |      CHPOINT        |      CHPOINT       |
|      LISTREEL     |      LISTREEL       |      LISTREEL      |
|       MCHAML      |       ______        |       MCHAML       |
----------------------------------------------------------------


    Note 1 :
    __________

    When the OBJET2 object is omitted, the ATG operator calculates
 the arctangent of the OBJET1 object (ENTIER or FLOTTANT type).

    Note 2 :
    __________

    When the ATG operator calculates the arctangent of a CHPOINT,
 it replaces each value of the CHPOINT with its arctangent. The
 RESU1 object is thus of CHPOINT type and has the same structure
 as OBJET2.

    Note 3 :
    __________

    When the ATG operator calculates the arctangent of a CHPOINT
 type OBJET1 divided by the CHPOINT type OBJET2, each value of
 OBJET1 is divided by the corresponding value of OBJET2 if it
 exists (otherwise, an angle of +- 90 degrees is given), then the 
 arctangent is taken. In this case, the RESU1 object is of CHPOINT
 type and has the same structure as OBJET2.

    Note 4 :
    ________

    For fields by elements , the ATG operator calculates only the
arctangent of the OBJET1 object. There is no OBJET2 object. The ATG
operator replaces each value of the MCHAML with its arctangent.