rsp_x_ functions generate a vector of assignment
terms and can be used to subset or condition a supplied (re)SPECIATE
data.frame.
Most commonly, the rsp_x_ functions accept a single input, a
(re)SPECIATE data.frame and return a logical vector of
length nrow(x), identifying species of interest as
TRUE. So, for example, they can be used when
subsetting in the form:
subset(rsp, rsp_x_nalkane(rsp))
... to extract just n-alkane records from a supplied respeciate
object rsp.
However, some accept additional arguments. For example, rsp_x_copy
also accepts a reference data set, ref, and a column identifier,
by, and tests rsp$by %in% unique(ref$by).
rsp_x_copy(rsp, ref = NULL, by = "species_id")
rsp_x_nalkane(rsp)
rsp_x_btex(rsp)a respeciate object, a data.frame of (re)SPECIATE
profiles.
(rsp_x_copy only) a second respeciate object, to
be used as reference when subsetting (or conditioning) rsp.
(rsp_x_copy only) character, the name of the column
in ref to copy when subsetting (or conditioning) rsp.
rsp_x_copy outputs can be modified but, by default, it
identifies all species in the supplied reference data set.
rsp_x_nalkane identifies (straight chain) C1 to C40 n-alkanes.
rsp_x_btex identifies the BTEX group of aromatic hydrocarbons
(benzene, toluene, ethyl benzene, and M-, O- and P-xylene).