Exclude/hide columns in a dataset
mda.exclcols(x, ind)dataset (data frame or matrix).
indices of columns to exclude (numbers, names or logical values)
dataset with excluded columns
The method assign attribute 'exclcols', which contains number of columns, which should be excluded/hidden
from calculations and plots (without removing them physically). The argument ind should contain
column numbers (excluding already hidden), names or logical values.