Creating custom report functions
Report authors create report expressions using
the expression editor. The expression editor provides a list of functions
that can be used in expressions. In addition to the functions that
are available by default, such as Today(), ReportDate() or ReportName(),
you can create custom functions and make them available to report
authors by defining report function libraries.
All functions available through the expression editor must be identified in the function definition service, a series of files that tells the expression editor what functions are defined. Report function collections are provided to report authors through dynamic load libraries on Windows operating systems, in shareable libraries on UNIX operating system, or in shared object files on the Linux® operating system.
Many types of function metadata definitions are shared among IBM® Cognos® applications and their components. Only the requirements for defining custom report functions are outlined in this chapter.
To make custom report functions available to report authors, you:
- Build a custom report functions library Building a custom report functions library
- Register the report functions library Registering custom report functions
- Install the custom report functions Installing a custom report functions library
For an example, see Example of a custom report functions implementation.