Gets the indices of units by their names.
# S3 method for UnitNamesFile
indexOf(this, pattern=NULL, names=NULL, ...)A pattern to be used for identifying unit names of
interest. If NULL, no regular expression matching is done.
Names to be match exactly to the unit names.
Not used.
Returns a vector of integers in [1,N] where N is the number of units
in the underlying annotation chip type file.
*getUnitNames().
For more information see UnitNamesFile.