importFrom("grDevices", "grey", "hsv")
importFrom("methods", "is")
importFrom("stats", "cor", "cor.test", "dist", "hclust", "lm",
           "na.omit", "pf", "prcomp", "predict")
import(grid, lattice, vcd, barcode, MASS, colorspace)
export(gpairs, corrgram)
