2. Syntax

/interspectrum
/tran_gene = DYNA_ISS_VARI (
    ◆/EXCIT_SOL = _F (
           ◆ | ACCE_X = function,
             | ACCE_Y = function,
             | ACCE_Z = function,
        ),
      /NB_FREQ = int,
    ◇ PRECISION = float (default: 0.999),
    ◇ ISSF =/"OUI ",
             /"NON" (by default),
    ◆ INTERF = _F (
         ◆ GROUP_NO_INTERF = grno,
         ◆ MODE_INTERF =/"CORP_RIGI ",
                         /"TOUT ",
                         /"QUELCONQUE ",
      ),
    ◆ MATR_COHE = _F (
         ◆ TYPE =/"MITA_LUCO ",
                  /"ABRAHAMSON ",
                  /"ABRA_ROCHER ",
                  /"ABRA_SOLMOYEN ",
         # If: equal_to (" TYPE ", 'MITA_LUCO')
             ◆ VITE_ONDE = float,
             ◇ PARA_ALPHA = float (default: 0.1),
      ),
    ◇ UNITE_RESU_FORC = unit (default: 33),
    ◇ UNITE_RESU_IMPE = unit (default: 32),
    ◇ TYPE =/"BINAIRE ",
             /"ASCII" (by default),
    ◆ MATR_GENE = _F (
         ◆ MATR_MASS = matr_asse_gene_r,
         ◆ MATR_RIGI = matr_asse_gene_r/matr_asse_gene_c,
         ◇ MATR_AMOR = matr_asse_gene_r/matr_asse_gene_c,
      ),
    ◇ INFO =/1 (by default),
             /2,
    # If: exists (" EXCIT_SOL ")
        ◇ & FREQ_MAX = float,
          & FREQ_PAS = float,
    # If: exists (" NB_FREQ ")
        ◆ FREQ_INIT = float,
        ◆ FREQ_PAS = float,
        ◇ OPTION =/"TOUT" (by default),
                   /"DIAG ",
        ◆ NOM_CMP =/"DX",
                    /"DY",
                    /"DZ",
)

◆: mandatory
◇: optional
: present by default
&: together
/: only one among
|: several possible choices