Integrating the Equation Editor in a DTD
Arbortext Architect offers users an Equation Editor that has an equation image interface for creating structured equations using the American Mathematical Society (AMS) symbol set. The Equation Editor allows you to edit an equationimage representation of an equation in Arbortext Editor.
The elements of the equation are defined by an XML or
SGML fragment that you must reference in your document type definition (DTD). There are two types of fragments. The first fragment is a regular DTD fragment that includes the
Equation Editor elements. The second fragment includes the elements from a namespace (
www.arbortext.com/namespace/atieqn/). Generally, you can use the regular DTD fragment to include the
Equation Editor in your DTD. However, if your DTD contains elements with the same name as the
Equation Editor elements, then you can use the namespace fragment to ensure that the element names are unique.
The DTD fragments are located in the Arbortextpath\entities directory. The following files support the Equation Editor:
• atimath.elm — Regular DTD fragment to support the Equation Editor in SGML DTDs
• atimathns.elm — DTD fragment with namespace prefixes to support the Equation Editor in SGML DTDs
• atimathx.dtd — Regular DTD fragment to support the Equation Editor in XML DTDs
• atimathns.dtd — Namespace DTD fragment to support the Equation Editor in XML DTDs
To make the Equation Editor available for your document type, add the appropriate entity declaration to your DTD.

When incorporating these fragments into a DTD, the equation wrapper element in the user's DTD must have a content model that allows empty content, or there will be parsing errors when Check Completeness is run.

To integrate the Equation Editor in your DTD:
1. Open Arbortext Architect, and then choose > to open the DTD Editor.
2. Add the appropriate entity declaration for the DTD fragment you want to use in your DTD.
For example, if you want to add the regular DTD fragment to an XML DTD you would typically add the following declaration:
<!ENTITY % atimath PUBLIC
"//ArborText//ELEMENTS XML Math Equation Structures//EN" "atimathx.elm">
%atimath;
3. Next, add entries for equation elements to existing content models in your DTD to indicate where each of the two types of equations is allowed.
For the regular DTD fragment, the element for display equations is named fd, and the element for inline equations is named f. For the namespace DTD fragment, the element for display equations is named atieqn:fd, and the element for inline equations is named atieqn:f.
4. Save your changes and exit the DTD Editor.