The Calculate Variable Task lets you use different kind of math operations to modify and existing Variable.
Store value in Variable...
First you select an existing Variable to store the new value in.
Result box
Here you can preview the future value of the next calculation.
Left and right hand value
You can choose to either work with the current Variable, one or two other Variables or just two other values. By combining different settings you have the following choices:
•VariableX = VariableY (math operation) VariableZ
•VariableX = VariableX (math operation) Value1
•VariableX = VariableY (math operation) Value1
•VariableX = Value1 (math operation) VariableX
•VariableX = Value1 (math operation) VariableY
•VariableX = Value1 (math operation) Value2
Operation
The following math operations are available: Addition, Subtraction, Multiplication and Division
Validate value when saving
If checked, VisualCron will validate the value with the value type. Leave not checked if you are using a Variable as value and the Variable is not yet set.