d9.08.01 Computer description of CALC_ESSAI# 1. Introduction 2. Launch, interactive and non-interactive mode 2.1. Retrieving pre-declared concepts 2.2. Launch in non-interactive mode 2.3. Launch in interactive mode 3. cata_ce.py file: catalogs 3.1. CalcessAIObjects Class Description 3.2. ModeMECA Class Description 3.3. DynaHarmo class 3.4. CaraElem classes, Material field 3.5. InterSpectre class 3.6. Tempo class 3.7. Model class 4. Description of generic graphics tools 4.1. TabbedWindow class 4.2. Interactive MessageBox class 4.3. ScrollList class 4.4. VisuSpectrum class 4.5. ParamMode ICouple, ParamMode LMME, and ParamProjMesuModal classes 4.6. Observation Window class 5. Validation of graphical tools and call tree 5.1. Window for viewing deformations and MAC 5.2. Identifying efforts 5.3. Data expansion 5.4. Structural modification 5.5. Calculations of interspectra, autospectra and transfer functions