This indicates the procedure for populating the values of a field. When you are processing a transaction that would use the user defined field, the value of the UDF can be populated in the 'User Defined Field/Field Name to Value Definition' screen that is loaded from the Contract Input screen or the Function Id screen. The value for the field can be populated based on certain conditions, which can be defined as statements of code by the user. Check against 'Derivation Allowed' to specify that the value of a field has to be populated based on certain conditions.

Description of the illustration derivation.png