Average expression values for duplicated/redundant genes

Takes an average, potentially on a different scale given by fun.natural of some genes. The average is then transformed with fun.cycle.

primerAverage(fd, geneGroups, fun.natural = expavg,
  fun.cycle = logshift)

Arguments

fd	SingleCellAssay or subclass
geneGroups	character naming a column in the featureData that keys the duplicates
fun.natural	transformation to be used to collapse the duplicate expression values
fun.cycle	transformation to be used after collapsing

Value

averaged version of fd.

Note

This code needs to be tested more extensively after a refactoring. Caveat calculator.