Macro language


These pages describe the Metview Macro language. Macro was developed before Python became popular, but has similar principles and syntax. As the Python language and ecosystem has become so well-featured, you may wish to consider using Metview’s Python API instead of the Macro language.

A macro language was part of the first design specification of Metview. It is designed to perform data manipulation and plotting from within the Metview system environment. A language is the best “user interface” to describe very complex sequences of actions, particularly if the flow of action is conditional. It also provides a common means to express the mathematical formulae used when performing data manipulations.

The Metview Macro language was designed to be as easy to get started with as a script language (e.g. UNIX shell) and as powerful as a modern computer language. To be as simple as a shell language implies that no variable declarations or program units should be required. This feature is achieved through the implementation of typeless variables, a benefit of object-oriented languages. To be as complex as a computer language implies support for variables, flow control, functions and procedures, I/O and error control.

The Metview Macro language provides an easy, powerful and comprehensive way for a researcher to manipulate and display meteorological data. It extends the use of Metview into an operational environment as it enables a user to write complex scripts that may be run with any desired periodicity.