The Calculate element can arithmetically manipulate Variables, whereby the I/O remains unmodified.

This Flow Control element can apply standard arithmetic (+,-,*,/) onto a Variable. Furthermore, the modulo (%) and exponentiation (^) methods are implemented in Lua 5.1. To edit the formula fill in the Formula field in the Properties. Please note that Variables are called with cow.VariableName.
Computation with a constant
cow.VariableName = cow.VariableName + ( any standard arithmetic symbol ) constant
Computation with a other Cow Variable
cow.VariableName = cow.VariableName + ( any standard arithmetic symbol ) cow.VariableName

Recall that a calculation of a Variable of type decimal and a Variable of type integer returns a Variable of type decimal.

Properties Window

The Variable factor is passed to the logic BoxManipulation. Factor is used as the coarse factor for the selected processor Coarse.
Here the Variable called factor is of type integer with default value two. To see how to set up and use a Variable follow the link.
After clicking into the grey part of the element Group the properties window displays the current value of the Variable factor.
The Calculate element displays the computation. Here the sum of the Variable factor and one is written back to the Variable factor.
Input Description
FirstInput Input is passed along and triggers Calculate
Output Description
FirstOutput Output which is unmodified