plotPM(x, which   = "", size    = 0, transfo = NULL, method  = mean, names   = "namepart", beside  = TRUE, col     = c("red", "blue"), legend  = c("PM","MM"), las     = 2, ylab    = "mean intensities", dev     = "screen", outfile = "PMPlot", w       = 540, h       = 540, ...)DataTreeSet.validData.FALSE, mean intensities are portrayed as stacked bars, 
   and if TRUE the columns are portrayed as juxtaposed bars.barplot.data
 for an object of class DataTreeSet. For names=NULL full column names of slot data will be displayed while for 
 names="namepart" column names will be displayed without name extension. If names
 is a vector of column names, only these columns will displayed as pmplot.
pmplot