'''OpenMath''' (http://www.openmath.org/) is a standard for exchange of mathematical objects, currently (2008) at version 2. In the future, OpenMath3 is expected to be equivalent to strict Content-[MathML]3; both of these standards are under construction. It is mostly MathML that has been changed to match OpenMath. Basic OpenMath tags (node types): OMI: Integer OMF: Floating-point number (64-bit IEEE, i.e., a [double]) OMV: Variable OMS: Symbol defined in some external ''Content Dictionary'' (CD). OMA: Application (like function application) Composite OpenMath expressions are usually constructed as an OMA whose first child is the symbol denoting the operation or function, e.g. 2 for [expr]'s 2+3.4e5. If parsed by [a little XML parser] (or [tdom]), this (modulo whitespace) comes out as OMA {} {{OMS {cd arith1 name plus} {}} {OMI {} {{#text 2}}} {OMF {dec 3.4e5} {}}} which is not too onerous to process. There are also some more advanced tags: OMSTR, OMB: Strings and bytearrays OMBIND, OMBVAR: Used when binding variables (like ''x'' bound by the integral in ∫''x''² d''x''). OMATTR, OMATP: Used for putting attributions on subexpressions. OME: Errors OMFOREIGN: Foreign format data OMR: References (for sharing subexpressions, much like [Tcl_Obj]s can be shared) ---- !!!!!! %| [Category Mathematics] | [Category Data Serialization Format] |% !!!!!!