Principle of the test
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Validation consists in:


* define a SIEF_R field using linear formulas based on space.


* assign the SIEF_R field on a mesh of solid elements.


* use PROJ_CHAMP to project field SIEF_R (3D) so as to obtain a field SIEF_R (DKT_global) on the subpoints of surface elements. Attention this field is in the same coordinate system as the initial field (therefore the global coordinate system), so it does not correspond to a field SIEF_R for a surface element that must be expressed in the local coordinate system.


* compare field SIEF_R (DKT_global) to a field calculated at the sub-points using the formulas previously defined, these 2 fields are expressed in the same coordinate system.


* use MODI_REPERE to change the coordinate system to field SIEF_R (DKT_global), by putting it in the local coordinate system of the surface elements and obtain a true SIEF_R (DKT).


* compare field SIEF_R (DKT) to a field calculated at the sub-points using the formulas previously defined but expressed in the local coordinate system of surface elements.