3 Free Format Input
This chapter describes the XML-based input format used by FEBio. Since this format follows standard XML conventions, the files can be viewed with any file viewer that supports XML files. Since the free format input file is a text file, it can be edited with any text editor.
An XML file is composed of a hierarchical list of elements. The first element is called the root element. Elements can have multiple child elements. All elements are enclosed by two tags: a tag defining the element and an end tag. A simple example of an XML file might look like this:
<root> <child> <subchild> ... </subchild> </child> </root>
The value of an element is enclosed between the name and the end tag.
<element> here is the value </element>
Note that the XML format is case-sensitive.
XML elements can also have attributes in name/value pairs. The attribute value must always be quoted using quotation marks (") or apostrophes (') [E] [E] Support for apostrophes was not added until FEBio version 2.1..
<element attr="value">...</element> <element attr='value'>...</element>
If an XML element has no value, an abbreviated syntax can be used. The following two lines are identical.
<element [attribute list]></element>
<element [attribute list]/>
Comments can be added as follows.
<!-- This is a comment -->
The first line in the document – the XML declaration – defines the XML version and the character encoding used in the document. An example can be:
Table of contents
- Section 3.1 Free Format Overview
- Section 3.2 Module Section
- Section 3.3 Control Section
- Section 3.4 Globals Section
- Section 3.5 Material Section
- Section 3.6 Mesh Section
- Section 3.7 MeshDomains Section
- Section 3.8 MeshData Section
- Section 3.9 Initial Section
- Section 3.10 Boundary Section
- Section 3.11 Rigid Section
- Section 3.12 Loads Section
- Section 3.13 Contact Section
- Section 3.14 Constraints Section
- Section 3.15 Discrete Section
- Section 3.16 Step Section
- Section 3.17 LoadData Section
- Section 3.18 Output Section