intervalValueCalculate | R Documentation |
Calculates a single value that is a function of an individual's values for a response over a specified time interval
Description
Splits the values of a response into subsets corresponding
individuals and applies a function that calculates a single
value from each individual's observations during a specified
time interval. It includes the
ability to calculate the observation that corresponds to
the calculated value of the function.
Usage
intervalValueCalculate(response, weights=NULL, individuals = "Snapshot.ID.Tag",
FUN = "max", which.obs = FALSE, which.levels = NULL,
start.time=NULL, end.time=NULL, times.factor = "Days",
suffix.interval=NULL, data, sep=".", na.rm=TRUE, ...)
Arguments
response |
A character giving the name of the column in
data from which the values of FUN are to be calculated.
|
weights |
A character giving the name of the column in
data containing the weights to be supplied as w
to FUN .
|
individuals |
A character giving the name(s) of the
factor (s) that define the subsets of the data for
which each subset corresponds to the response value for an
individual.
|
FUN |
A character giving the name of the function
that calculates the value for each subset.
|
which.obs |
A logical indicating whether or not to determine
the observation corresponding to the value of the function,
instead of the value of the function itself.
|
which.levels |
A character giving the name of the
factor whose levels are to be identified as
the level of the observation whose value matches the
value of the function.
|
start.time |
A numeric giving the times,
in terms of levels of times.factor , that will give a
single value for each Snapshot.ID.Tag and that will
be taken as the observation at the start of the interval for
which the growth rate is to be calculated. If
start.time is NULL , the interval will start
with the first observation.
|
end.time |
A numeric giving the times,
in terms of levels of times.factor , that will give a
single value for each Snapshot.ID.Tag and that will be
taken as the observation at the end of the interval for which
the growth rate is to be calculated. If end.time is
NULL , the interval will end with the last observation.
|
times.factor |
A character giving the name of the column in
data containing the factor for times at which the data was
collected. Its levels should be numeric values stored as
characters.
|
suffix.interval |
A character giving the suffix to be
appended to response to form the
name of the column containing the calculated values. If it is
NULL then nothing will be appended.
|
data |
A data.frame containing the column from which the
function is to be calculated.
|
na.rm |
A logical indicating whether NA values
should be stripped before the calculation proceeds.
|
sep |
A character giving the separator to use when the
levels of individuals are combined. This is needed to avoid
using a character that occurs in a factor to delimit
levels when the levels of individuals are combined to
identify subsets.
|
... |
allows for arguments to be passed to FUN .
|
Value
A data.frame
, with the same number of rows as there are
individuals
, containing a column for the individuals
,
a column with the values of the function for the individuals
,
and a column with the values of the times.factor
. The name of
the column with the values of the function will be result of
concatenating the response
, FUN
and, if it is not
NULL
, suffix.interval
, each separated by a full stop.
Author(s)
Chris Brien
See Also
intervalGRaverage
, intervalGRdiff
, intervalWUI
, splitValueCalculate
, getDates
Examples
data(exampleData)
Area.smooth.max <- intervalValueCalculate("Area.smooth",
start.time = 31, end.time = 35,
suffix.interval = "31to35",
data = longi.dat)