Syntax
=====

.. code-block:: text

    /Cham_elem
    /fiel_no = CALC_FATIGUE (
        ◆ TYPE_CALCUL =/"CUMUL_DOMMAGE ",
                        /"FATIGUE_MULTI ",
                        /"FATIGUE_VIBR ",
        # If: equal_to (" TYPE_CALCUL ", 'CUMUL_DOMMAGE')
            ◆ OPTION =/"DOMA_ELNO_SIGM ",
                       /"DOMA_ELGA_SIGM ",
                       /"DOMA_ELNO_EPSI ",
                       /"DOMA_ELGA_EPSI ",
                       /"DOMA_ELNO_EPME ",
                       /"DOMA_ELGA_EPME ",
            # If: equal_to (" OPTION ", 'DOMA_ELNO_SIGM') or equal_to (" OPTION ", 'DOMA_ELGA_SIGM')
                ◆ HISTOIRE = _F (
                     ◆ RESULTAT = evol_noli/dyna_trans/evol_elas,
                     ◇ EQUI_GD = "VMIS_SG ",
                  ),
            # If: not equal_to (" OPTION ", 'DOMA_ELNO_SIGM') and not equal_to (" OPTION ", 'DOMA_ELGA_SIGM')
                ◆ HISTOIRE = _F (
                     ◆ RESULTAT = evol_noli/dyna_trans/evol_elas,
                     ◇ EQUI_GD = "INVA_2_SG ",
                  ),
            ◇ & DOMMAGE =/"WOHLER ",
                          /"MANSON_COFFIN ",
                          /"TAHERI_MANSON ",
                          /"TAHERI_MIXTE ",
              & MATER = subdue,
            ◇ TAHERI_NAPPE = formula/tablecloth,
            ◇ TAHERI_FONC = formula/tablecloth/function,
        # If: equal_to (" TYPE_CALCUL ", 'FATIGUE_VIBR')
            ◆ OPTION =/"DOMA_ELNO_SIGM ",
                       /"DOMA_ELGA_SIGM ",
            ◆ CORR_SIGM_MOYE =/"GOODMAN ",
                               /"GERBER ",
            ◆ HISTOIRE = _F (
                 ◆ RESULTAT = evol_noli/evol_elas,
                 ◆ MODE_MECA = meca fashion,
                 ◆ NUME_MODE = int,
                 ◇ FACT_PARTICI = float (default: 1.0),
                 ◇ EQUI_GD = "VMIS_SG ",
              ),
            ◇ & DOMMAGE = "WOHLER" (or not specified),
              & MATER = subdue,
        # If: equal_to (" TYPE_CALCUL ", 'FATIGUE_MULTI')
            ◆ TYPE_CHARGE =/"PERIODIQUE ",
                            /"NON_PERIODIQUE ",
            ◆ OPTION =/"DOMA_ELGA ",
                       /"DOMA_NOEUD ",
            ◆ RESULTAT = evol_noli/evol_elas,
            ◇ CHAM_MATER = mater_field,
            ◆ MAILLAGE = mesh,
            ◆/GROUP_MA = grma,
              /GROUP_NO = grno,
            ◇ COEF_PREECROU = float (default: 1.0),
            # If: equal_to (" TYPE_CHARGE ", 'PERIODIQUE')
                ◆ CRITERE =/"MATAKE_MODI_AC ",
                            /"DANG_VAN_MODI_AC ",
                            /"VMIS_TRESCA ",
                            /"FORMULE_CRITERE ",
                # If: (equal_to (" CRITERE ", '",' MATAKE_MODI_AC ') or equal_to (" CRITERE ",' DANG_VAN_MODI_AC '))
                    ◆ METHODE = "CERCLE_EXACT" (or not specified),
                # If: (equal_to (" CRITERE ", 'FORMULE_CRITERE'))
                    ◆ FORMULE_GRDEQ = formula/function,
                    ◆ COURBE_GRD_VIE =/"WOHLER ",
                                       /"MANSON_COFFIN ",
                                       /"FORM_VIE ",
                    ◇ FORMULE_CRITIQUE = formula/function,
                    # If: (equal_to (" COURBE_GRD_VIE ", 'FORM_VIE'))
                        ◆ FORMULE_VIE = formula/function,
                ◇ & INST_INIT_CYCL = float,
                  & INST_CRIT =/"RELATIF ",
                                /"ABSOLU ",
                # If: (equal_to (" INST_CRIT ", 'RELATIF'))
                    ◇ PRECISION = float (default: 1e-06),
                # If: (equal_to (" INST_CRIT ", 'ABSOLU'))
                    ◆ PRECISION = float,
            # If: equal_to (" TYPE_CHARGE ", 'NON_PERIODIQUE')
                ◆ CRITERE =/"MATAKE_MODI_AV ",
                            /"DANG_VAN_MODI_AV ",
                            /"FATESOCI_MODI_AV ",
                            /"FORMULE_CRITERE ",
                            /"VMIS_TRESCA ",
                # If: (not equal_to (" CRITERE ", 'VMIS_TRESCA'))
                    ◆ PROJECTION =/"UN_AXE ",
                                   /"DEUX_AXES ",
                    ◇ DELTA_OSCI = float,
                # If: (equal_to (" CRITERE ", 'FORMULE_CRITERE'))
                    ◆ FORMULE_GRDEQ = formula/function,
                    ◆ COURBE_GRD_VIE =/"WOHLER ",
                                       /"MANSON_COFFIN ",
                                       /"FORM_VIE ",
                    # If: (equal_to (" COURBE_GRD_VIE ", 'FORM_VIE'))
                        ◆ FORMULE_VIE = formula/function,
        ◇ INFO =/1 (by default),
                 /2,
    )
    
    ◆: mandatory
    ◇: optional
    : present by default
    &: together
    /: only one among
    |: several possible choices