ungriddedTableDef — Defines a table of data, each with independent coordinates
ungriddedTableDef : [name], [utID], [units]
(description?,
(provenance? | provenanceRef?)
, uncertainty?, dataPoint+)
name(optional) - the name of the ungridded table
utID(optional) - an internal, document-unique XML name for the gridded table
units(optional) - the units of measure for the table values
An ungriddedTableDef contains points that are not in an orthogonal grid pattern; thus, the independent variable coordinates are specified for each dependent variable value. This table definition is specified separately from the actual function declaration and requires an XML identifier attribute so that it may be used by multiple functions.