Formulas and deferred parameters

A recipe formula is made up of a set of variables used to control process values such as time, temperature, and quantities of ingredients. By including a formula in a recipe, you can use the same recipe to make variations of a product. This is especially useful if the same sequence of events will be used every time but the variables used by the logic will be different. In our example, we go through the same steps every time we want to make a batch of paint: add base, add color, mix, and drain. However, we can make different colors or shades by altering which color is added and how much base and color are used. Formulas can override the default input parameter values in a recipe and let you specify any value you need depending on the batch to be produced.

When setting up formulas for your recipes you can:

• Create recipe parameters at the operation, unit procedure, or procedure level. (Create the parameter at the lowest level at which it is used.) The type of value at the different levels must match. That is, if the phase input parameter to be deferred is an integer, then the recipe input parameter must also be an integer.
• Modify individual phase or recipe parameters to defer to a higher level in the recipe to obtain a value for the parameter. (The higher level will have formulas that provide values for the parameters.)
• Define formulas for different combinations of values to be used by deferred parameters. Parameter values in formulas can be easily selected and modified at batch creation time. Formulas can be created at any recipe level that gets assigned to a Batch Executive.