The problem type is defined using a directory with the its name and a set of files. The directory with the problem type will be located in the problemtypes directory in the GiD distribution, or in a subdirectory of it. This set of files define the problemtype and contain the full functionality for customizing the pre-process. The main files that configure the problem type are shown in the table below.

File extension



Main configuration file of the data tree, XML-based.


Information for data input file. It should be an empty file


Main TCL file, initialization


Conditions definition. It should not be modified by the user


Output description to the file of analysis

  • Main configuration file of the data tree, XML-based.

The main configuration file in XML format contains the definition of all the data (except the geometry) necessary to perform an analysis. It is defined in XML format with the extension .spd (specific problem type data) and contains all the definition of all the data that defines the analysis like boundary conditions, loads, materials, loadcases, etc.

The syntax rules of the .spd file are very simple, logical, concise, easy to learn and to use. The file is human-legible, clear and easy to create. Moreover, the information is stored in plain text format. It can be viewed in all major of browsers, and it is designed to be self-descriptive.

The elements in a XML document form a tree-structure that starts at “the root” and branches to “the leaves” with different relationships between the nested elements. It allows to aggregate efficiently elements. CustomLib takes advantage of this hierarchical structure to convert automatically the main XML file to a physical tree on the GiD window. The XML elements can have attributes, which provide additional information about elements.

It is necessary to modify this XML document in order to add conditions, or general data to the problem type.

  • Main TCL file, initialization

A TCL initialization file is used to create complex windows or menus. Contains the initialization routines

  • Output description to the file of analysis

A TCL file located in the <scripts> folder determines the way in which the final information has to be written inside the input files that will be read by the solver.

  • Conditions file

File with extension .cnd is used but should not be modified by the problemtype creator.

  • Information for data input file

File .bas is not used it should be existing but void.

  • Several other TCL files