Determines the range of the data, which can possibly be trimmed before
calculating the extreme values. The robust range version is calculated on
the basis of the trimmed mean and variance (see Details).

If trim is zero (the default), the arithmetic mean of the
values in x is computed, as a numeric or complex vector of length
one. If x is not logical (coerced to numeric), numeric (including
integer) or complex, NA_real_ is returned, with a warning.

If trim is non-zero, a symmetrically trimmed mean is computed with a
fraction of trim observations deleted from each end before the mean
is computed.

Arguments

x

a numeric vector.

trim

the fraction (0 to 0.5) of observations to be trimmed from each
end of x before the mean is computed. Values of trim outside that
range are taken as the nearest endpoint. Default is 0 for
robust=FALSE and 0.2 for robust=TRUE

robust

logical, determining whether the robust or the convential
range should be returned.

na.rm

a logical value indicating whether NA values should be
stripped before the computation proceeds.

...

the dots are sent to RobRange and can be used to set
fac (See details).

Author

Werner Stahel, ETH Zurich (robust range) Andri Signorell
andri@signorell.net

Details

The R base function range returns the minimum and maximum value of a numeric
object. Here we return the span of a (possibly trimmed) numeric vector, say
the difference of maximum and minimum value.

If robust is set to TRUE the function determines the trimmed mean m
and then the "upper trimmed mean" s of absolute deviations from m,
multiplied by fac (fac is 3 by default). The robust minimum is then
defined as m-fac*s or min(x), whichever is larger, and similarly for the
maximum.