This class serves the same purpose as the flowFrame class from the flowCore package: to storequantitative data on cell populations from a single FCS run. The primary difference is in the un-derlying representation of the data. While flowFrame objects store the underlying data matrix inthe exprs slot as an R object, cytoframe objects store the matrix (as well as the data from theother slots) in a C data structure that is accessed through an external pointer. This allows for greateroptimization of data operations including I/O, parsing, transformation, and gating.