3. Generalities#

This command makes it possible to test a scalar numerical value retrieved in a concept such as cham_no, cham_elem, map or result, in relation to a non-regression value and, when possible, against an analytical reference value, coming from an external source or from another calculation with Code_Aster.

Three types of numerical values can be tested:

  • a component of a field (cham_no, cham_elem, map or field that is part of a result),

  • a parameter contained in a result concept,

  • an overall value of a field [§ 4.4].

To test a field component, you must choose a field [§ 4.1] and then choose a component [§ 4.3].

To test a parameter, you must choose an order number [§ 4.1.4] and choose the name of the parameter.

The expected numerical value (real, complex, or integer) is provided in accordance with [§ 4.7].

Note about non-regression tests

A non-regression test is systematically performed in relation to a value calculated previously. The tolerance associated with this test ( TOLE_MACHINE ) must be very low and should not be greater than the default value. In particular, the value should be the same (at least 8 decimal places) across platforms. Moreover, this calculated value should only change when the algorithm is modified or corrected. Any other variation should alert the developer to the reliability of the programming.

Notes on testing in « generalized » data structures:

We can test the generalized components (displacements, speeds or accelerations of a transient in the modal space). However, caution should be exercised with this type of test. In fact, the value of a generalized component depends entirely on the mode norm. However, it is determined arbitrarily. So without prior standardization of the norms, the value of a generalized quantity is arbitrary. Finally, there is no possibility in Code_Aster to set the direction of a mode. For a multiple mode, this means that, even once the modes have been normalized, a generalized quantity can take any value. In the case of a simple mode, it can be oriented in one direction or in the opposite direction. We then obtain a generalized value or its opposite.