Replaces all uses of a given meta identifier attribute value with another value.

In SBML, object "meta" identifiers are of the XML data type ID; the SBML object attribute itself is typically named metaid. All attributes that hold values referring to values of type ID are of the XML data type IDREF. They are also sometimes informally referred to as "metaid refs", in analogy to the SBML-defined type SIdRef.

This method works by looking at all meta-identifier attribute values, comparing the identifiers to the value of oldid. If any matches are found, the matching identifiers are replaced with newid. The method does not descend into child elements.

Parameters

oldid	the old identifier.
newid	the new identifier.