Toggle Names Used in Decompositions

This tells you how AnalyseGE makes up names or toggles when you ask it to show a decomposition. The toggle names used by AnalyseGE are different for intelligent and complete decompositions.

[Remember that any decomposition in a Formula is an intelligent one. But decompositions in linearised Equations can be complete or intelligent.]

When you are decomposing a selected expression, the last toggle shows the values of the whole expression. AnalyseGE uses "EXP" (expression) as the name for this toggle.

Below we describe how the names of other toggles are made.

Intelligent Decomposition (Formula or Equation)

When doing an intelligent decomposition, AnalyseGE makes up toggle names which are based on the names of the Coefficients and Variables in the different expressions.

•If the values corresponding to a toggle consists of a single Coefficient or Variable, AnalyseGE prefers to make the toggle name the same as the name of this Coefficient or Variable.

•If the values corresponding to a toggle is a more complicated expression, AnalyseGE puts e<d>_ at the start of the toggle name and then tries to use the name of the first Coefficient or Variable occurring in the expression to complete the toggle name. The "e<d>_" at the start is to remind you that the values of the toggle you are looking at in ViewHAR are the values of an expression which starts with the Coefficient or Variable whose name is at the end of the toggle name. In this case, the values you are looking at in ViewHAR are those of an expression which usually involves two or more Coefficients and Variables and some arithmetic operation. Here the "d" part is one (or more) digits, starting from 1 so you may see toggle names like "e1_V3BAS" and "e2_x3" or even (if there are many different toggles) "e12_x3".

Example

Equation E_x3 # Source-specific commodity demands #

(all,c,COM)(all,s,SRC) x3(c,s) - a3(c,s) =

x3_s(c) - SIGMA3(c) * [p3(c,s) + a3(c,s) - p3_s(c)] ;

If you do an intelligent decomposition of the RHS of this equation, the toggle names are "x3_s" and "e1_SIGMA3". This is because the values of these toggles are

x3_s(c) - just those of a single Coefficient,

-SIGMA3(c) * [p3(c,s)+a3(c,s)-p3_s(c)], which is a complicated expression.

If you select the expression SIGMA3(c) * [p3(c,s)+a3(c,s)-p3_s(c)] and ask for an intelligent decomposition, the toggle names are "SIGMA3", "e1_p3" and "EXP". This is because the values of these toggles are

SIGMA3(c), which are those of a single Coefficient,

p3(c,s)+a3(c,s)-p3_s(c), which is a complicated expression,

the whole expression (toggle is "EXP").

We are grateful to Steven Rose who suggested that we use something like "e1_" at the start of toggle names whose values are those of a complicated expression to alert users that there is an expression involved. [These "e1_" toggle names were introduced in Version 2.80 (December 2004) of AnalyseGE. Prior to that, the toggle name for a complicated expression was usually the name of the first Coefficient or Variable occurring in the expression. This obscured the fact that an expression was involved.]

Complete Decomposition of All or Part of an Equation

The discussion below applies if you are doing a complete decomposition of all of an Equation, of one side of an Equation, or of a selected expression in an Equation.

When you do a complete decomposition of all or part of an equation, AnalyseGE always uses the names of the variables as the toggle names. This is because you can think of a complete decomposition as a decomposition by variables. [AnalyseGE never puts "e1_" or similar at the start of the toggle names when doing a complete decomposition.]

Example

Equation E_x3 # Source-specific commodity demands #

(all,c,COM)(all,s,SRC) x3(c,s) - a3(c,s) =

x3_s(c) - SIGMA3(c) * [p3(c,s) + a3(c,s) - p3_s(c)] ;

If you do a complete decomposition of the RHS of this equation, the toggle names are the names of the variables on the RHS, namely "x3_s", "p3", "a3" and "p3_s".

The only time this cannot happen is when a variable has more than 12 characters in its name when AnalyseGE takes the first 9 letters of the name and adds up to 3 digits at the end. For example, if you have a variable with name "veryverylongvar" then AnalyseGE will use something like "veryveryl2" as the toggle name.

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

Link to full GEMPACK Manual

Link to GEMPACK homepage