Validating data

range()

{base}

return vector of minimum and maximum

max()

{base}

compute maxima of input values

duplicated()

{base}

determine which elements of a vector or data frame are duplicates

summary()

{base}

return summary of model fitting functions

unique()

{base}

return vector with duplicate elements removed

which()

{base}

give TRUE indices of logical object

min()

{base}

compute minima of input values

The end!