Syntax
=====

.. code-block:: text

    char_ther = AFFE_CHAR_THER (
        ◆ MODELE = model,
        ◇ DOUBLE_LAGRANGE =/"OUI" (by default),
                            /"NON ",
          | EVOL_CHAR = evol_char,
        ◆ | TEMP_IMPO = _F (
               ◆ | ALL = "YES" (or not specified),
                 | GROUP_MA = grma,
                 | GROUP_NO = group,
               ◇ SANS_GROUP_MA = Grma,
               ◇ SANS_GROUP_NO = big,
               ◆ | TEMP = float,
                 | TEMP_MIL = float,
                 | TEMP_SUP = float,
                 | TEMP_INF = float,
            ),
          | SOURCE = _F (
               ◇/TOUT = "OUI" (or not specified),
                 /GROUP_MA = grma,
               ◆/SOUR_CALCULEE = cham_elem/cham_no,
                 /SOUR = float,
            ),
          | STREAM_REP = _F (
               ◆/TOUT = "OUI" (or not specified),
                 /GROUP_MA = grma,
               ◆ | FLUN = float,
                 | FLUN_INF = float,
                 | FLUN_SUP = float,
                 | CARA_TORSION = table,
            ),
          | EXCHANGE = _F (
               ◆/TOUT = "OUI" (or not specified),
                 /GROUP_MA = grma,
               ◆ | COEF_H = float,
                 | COEF_H_INF = float,
                 | COEF_H_SUP = float,
               ◇ & TEMP_EXT = float,
               ◇ & TEMP_EXT_INF = float,
               ◇ & TEMP_EXT_SUP = float,
            ),
          | EXCHANGE_WALL = _F (
               ◆/GROUP_MA_1 = grma,
                 /FISSURE = fiss_xfem,
               ◆/GROUP_MA_2 = grma,
               # If: not exists (" FISSURE ")
                   ◆ COEF_H = float,
                   ◇ TRAN = float,
               # If: exists (" FISSURE ")
                   ◆/COEF_H = float,
                     /TEMP_CONTINUE = "OUI" (or not specified),
            ),
          | PRE_GRAD_TEMP = _F (
               ◆/TOUT = "OUI" (or not specified),
                 /GROUP_MA = grma,
               ◆ | FLUX_X = float,
                 | FLUX_Y = float,
                 | FLUX_Z = float,
            ),
          | DDL_LINK = _F (
               ◇ GROUP_NO = big,
               ◇ DDL =/"TEMP ",
                       /"TEMP_MIL ",
                       /"TEMP_INF ",
                       /"TEMP_SUP ",
                       /"H1",
               ◆ COEF_MULT = float,
               ◆ COEF_IMPO = float,
            ),
          | GROUP_LINK = _F (
               ◆/GROUP_MA_1 = grma,
                 /GROUP_NO_1 = grno,
               ◆/GROUP_NO_2 = grno,
                 /GROUP_MA_2 = grma,
               ◇ SANS_GROUP_NO = big,
               ◇ DDL_1 =/"TEMP" (by default),
                         /"TEMP_MIL ",
                         /"TEMP_INF ",
                         /"TEMP_SUP ",
                         /"H1",
               ◆ COEF_MULT_1 = float,
               ◇ DDL_2 =/"TEMP" (by default),
                         /"TEMP_MIL ",
                         /"TEMP_INF ",
                         /"TEMP_SUP ",
                         /"H1",
               ◆ COEF_MULT_2 = float,
               ◆ COEF_IMPO = float,
               ◇ TRAN = float,
               ◇ ANGL_NAUT = float,
               ◇ CENTRE = float,
            ),
          | UNIF_LINK = _F (
               ◆/GROUP_NO = grno,
                 /GROUP_MA = grma,
               ◇ DDL =/"TEMP" (by default),
                       /"TEMP_MIL ",
                       /"TEMP_INF ",
                       /"TEMP_SUP ",
                       /"H1",
            ),
          | FIELD_LINK = _F (
               ◆ CHAM_NO = cham_no,
               ◆ COEF_IMPO = float,
            ),
          | RADIATION = _F (
               ◆/TOUT = "OUI" (or not specified),
                 /GROUP_MA = grma,
               ◆ SIGMA = float,
               ◆ EPSILON = float,
               ◆ TEMP_EXT = float,
            ),
          | MAIL_LINK = _F (
               ◇ GROUP_MA_MAIT = Grma,
               ◆ | GROUP_MA_ESCL = grma,
                 | GROUP_NO_ESCL = grno,
               ◇ TRAN = float,
               ◇ ANGL_NAUT = float,
               ◇ CENTRE = float,
               ◇ ELIM_MULT =/"OUI" (by default),
                             /"NON ",
               ◇ DISTANCE_MAX = float,
               ◇ DISTANCE_ALARME = float,
            ),
          | CONVECTION = _F (
               ◆ VITESSE = cham_no,
            ),
        ◇ INFO =/1 (by default),
                 /2,
    )
    
    ◆: mandatory
    ◇: optional
    : present by default
    &: together
    /: only one among
    |: several possible choices