6. Activation of the new nonlinear law

Once the routines for preparing and calculating the nonlinear force have been created (dtmprep_noli_newf and dtmforc_newf), it is necessary to activate them by adding a « case »:

• In dtmprep_noli, dispatching to dtmprep_noli_newf based on the value of the RELATION keyword under the COMPORTEMENT factor keyword of DYNA_VIBRA.

• In dtmforc, routine responsible for calculating the force, based on the value of the NL_TYPE parameter, allowing to go through dtmforc_newf.