Pre-Simulation and Post-Simulation Values of Expressions

When you load an SLC file which is produced from a model whose TAB file contains Postsim statements, this SLC file contains both the pre-simulation and the post-simulation values of all normal Coefficients.

In this case, the values you see when you evaluate an expression may be pre-simulation or post-simulation ones, as explained under 1 and 2 below.

However, if you load an SLC file that contains no post-sim coefficient values, the values you see are always pre-simulation values. If you load a UDC or an AVC file, the values that you see are always post-sim values (UDC case) or the average of pre-sim and post-sim values (AVC case). So the rest of this topic is only relevant if you load an SLC file which contains both pre-sim and post-sim coefficient values.

If you have calculated post-simulation values, the long name on the Results header Rxxx begins with [Postsim] as a reminder.

1. Expression Selected from TABmate form

If you select the expression to evaluate from the TABmate form, which values you see depends on the menu options under the AnalyseGE menu item on the TABmate form.

If menu item Use Pre-sim Coeff Values is selected, pre-simulation values for the Coefficients will be used, so the result is the pre-simulation value of the expression.

If menu item Use Post-sim Coeff Values is selected, post-simulation values for the Coefficients will be used so the result is the post-simulation value of the expression.

If menu item Pre/Post-sim from TABLO Statement is selected (this is the one selected every time you open a new solution in AnalyseGE), the values depend on whether or not the TABLO statement you selected the expression from is a Postsim one.

•If the expression comes from a normal (as distinct from a Postsim) statement, the normal Coefficients are given their pre-simulation values when the expression is evaluated.

•If the expression comes from a Postsim statement, the normal Coefficients are given their post-simulation (that is, updated) values when the expression is evaluated.

•In all cases, Coefficients declared in a Postsim part of the TAB file are always given the same values, namely whatever values they hold when all Postsim statements are carried out on the third postsim pass of the simulation.

You can change the options setting under the AnalyseGE menu on the TABmate form several times during one run if you wish. For example, by doing that you can see the pre-simulation values of certain expressions and then later see the post-simulation values of the same expressions.

Note that the three menu items above are only relevant if you have loaded a Solution file and an associated SLC file that contains post-simulation values (as well as pre-simulation values). If the SLC file does not contain any post-simulation values, AnalyseGE knows that and ignores the three menu items above.

2. Evaluating Expressions from the AnalyseGE form

Alternatively, the values you see when you click on one of the Evaluate buttons on the AnalyseGE form may depend on whether you click on the Evaluate Presim or the Evaluate Postsim button. As above, the difference comes from which values are given to the normal (as distinct from Postsim) Coefficients, which are given their pre-simulation values when you click on the "Evaluate Presim" button but which are given their post-simulation values when you click on the "Evaluate Postsim" button.

[If you load an SLC file that contains both pre-sim and post-sim coefficient values, both Evaluate buttons will be enabled. However, if you load an SLC file that contains no post-sim coefficient values, only one will be enabled and its caption will be "Evaluate". Similarly, if you load a UDC or an AVC file, only one of the Evaluate buttons will be enabled and its caption will be "Evaluate".]

URL of this topic: www.copsmodels.com/webhelp/analysege/hc_prepostsimexpressionvalues.htm

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