User-Defined Variables

A powerful way of extending PetroVR's modeling capabilities is creating user-defined variables, i.e. additional variables not provided by the system, to be used in functions and calculations.

Like any other variable in PetroVR, user-defined variables are always associated to objects, so that they can be created at any of the following levels:

  • The Project
  • Reservoirs
  • Wells
  • Facilities
  • Rigs
  • Jobs
  • Well Groups

All Tree View nodes corresponding to these objects have a The User Tab, which is the place for creating and editing user-defined variables.

User-defined variable names are built on the same basis as other Variable names. For example, a variable called "Additional CapEx" defined in the User tab of a well completion "Producer 1" associated to a reservoir "Devonian A" would receive this full name:

Well Completion: Devonian A: Producer 1: Additional CapEx

Actually, user-defined variables need not be related to the object with which they are associated; their impact on the results will not change whether they are placed under a well or at the root of a project. However, this association with particular objects can help you to tidy up user-defined variables and keep the model easy to understand.

The default type for user-defined variables is numeric. However, as soon as you enter a value this is updated to match the type entered - for example, entering an alphanumeric string will automatically turn it into a Text variable; entering a function that yields a date value will set the type to Date; and so on. This works only once the first time: once the default type has been changed it will no longer be automatically updated to match new definitions.