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).
Range(x, trim = NULL, robust = FALSE, na.rm = FALSE, ...)
a numeric vector.
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
logical, determining whether the robust or the convential range should be returned.
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).
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.
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.