colorscheme(x) selects color scheme of graphical output. Function parameter NULL lists all available color schemes, 1 a color tuple of green and blue
2 a color tuple of dark green and turquoi, 3 a colorplaette as defined by RcolorBrewer
Convert data frame of counts to data frame of cases.
data frame must contain a column with frequencies (counts) as generated by
as.data.frame from a contingency table