Analysis envelopes

An analysis envelope is a stored envelope of results produced in way similar to other analysis options. I.e Analysis envelopes are requested by setting up an appropriate analysis task via the Analysis Wizard and then analysing this. The envelope is produced by comparing results from cases described in the syntax of a standard enveloping combination case. Since it is stored it is very much quicker to display than the alternative combination envelope that is produced by examining all effected analysis case results at the time of display. The disadvantage of analysis envelopes is that derivation of other results from those stored is not possible.

The specification of an analysis envelope includes a case description, that describes which cases are to be compared, and the result types for which envelopes are required. In the case of element results it is also necessary to specify whether an envelope is required at each node on the element or just at the worst position. Setting up an analysis envelope task produces several analysis cases: a case each for the maximum and minimum values for each position for each data type selected. Performing the analysis determines which permutation causes the maximum or minimum value for the data type at the position at each node or element.

Having produced the analysis envelope the results to which the envelope permutation refers plus coexistent values can be output in Graphic Views, as contours or diagrams, and in Output Views as tables of results.

Analysis envelope cases may be referred to by combination cases.