# scale (continous) variables
  # scale multiple variables simultaneously and get a reusable scaling model for applying to test data

  transformations <- preProcess(birdsVars) #what is done
  transformations
  scaledVars <- predict(transformations,birdsVars) # all on the same scale
  scaledVars
  print(xtable(scaledVars), type = "latex")
  predict(transformations,testing_x)

  knitr::kable(t(summary(scaledVars)))