Validating data

determine which elements of a vector or data frame are duplicates

duplicated()

{base}

give TRUE indices of logical object

which()

{base}

compute minima of input values

min()

{base}

return summary of model fitting functions

summary()

{base}

compute maxima of input values

max()

{base}

return vector of minimum and maximum

range()

{base}

return vector with duplicate elements removed

unique()

{base}

The end!