EMK:Formulae and Functions

Formulae can be entered as substitutes for specific values into most fields in EMarket to control the derivation of variable values at run time. A formula can contain any combination of:

• Constants
• Variables
• Operators
• Entities and Traits
• Functions

Constants

Constants can be:

• Numbers: Integers or Reals (e.g. 1, 2.5, -3), they can also be entered in scientific notation e.g. '3E+10'.
• Strings: Written inside double quotes e.g. "A Node"
• Dates: Must be enclosed in single quotes e.g '1/3/2004' or '14 April 2005'

Warning: The format for entering dates should compatible with the computer's local date (locality) setting

Variables

Variables can be regarded as user-defined Entity.Traits which can be defined in the Volatility Matrix or the Schedule. Previously defined variables can be used in formulae.

Note: EMarket provides a 'system' variable the user need not define: 'DateTime' which is of type 'Date' and gives the current simulation date as the model runs.

Operators

Operators are all pre-defined in EMarket. Their purpose is to separate a formula into parts that are then combined to give a single value.

The following operators are shown in descending order of precedence.

Operator	Meaning	Example	Parameter Type	Return Type
\	Integer Division	3\2 = 1	Real; Int	Int
%	Modulus	7%5 = 2	Real; Int	Int
/	Division	3/2 = 1.5	Real; Int	Real
*	Multiplication	5*4.2 = 21	Real; Int	Real
-	Subtraction	7-3.2 = 3.8	Real; Int	Real
+	Addition	3.5+1.5 = 5	Real; Int	Real