For astronomers with complex datasets the standard tools, such as PGPLOT, may not be sufficient for your needs. Instead for display of three-dimensional scalar data you should look towards IDL or DX.
IBM DX (Data Explorer) is the data visualisation package recommended by Starlink, particularly for the visualisation of three-dimensional scalar and vector data. The package is covered in detail in The DX Cookbook (SC/2). However, additional information about DX and documentation dealing with SX, the Starlink enhancements to DX, can be found in SUN/203.
The Interactive Data Language (IDL) is designed to be used for data analysis, visualization, and cross-platform application development. IDL may be available at your site, see your Starlink system administrator for details.
An Introduction to Visualisation Software for Astronomy, SG/8, provides a general overview of visualisation software for astronomers and includes details of a number of packages. The author of SG/8, Clive Davenhall, also maintains a web page covering visualisation software at http://www.roe.ac.uk/~acd/vissys/index.html.