get.reference.values: Get Reference Values for Aggregation Periods
In WillemMaetens/standaRdized: Standardized Index Calculation

Description Usage Arguments Details Value See Also Examples

View source: R/get.reference.values.R

Function to get the reference values for aggregation periods

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get.reference.values(date, ref.data, agg.length, agg.fun = "sum",
  ref.years = NULL, ref.length = 30, agg.na.thres = 10,
  agg.interpolation = c("none", "linear", "mean", "zeros"))

`date`	date for which the reference values from other years are determined
`ref.data`	an xts object containing daily reference data
`agg.length`	length of the aggregation period in days
`agg.fun`	function on x to apply to the aggregation data, default is 'sum'
`ref.years`	years to be used as reference period, default (NULL) is to use all years in ref.data. If ref.years is set to NA, ref.length is used to determine the reference period.
`ref.length`	if ref.years is null, the ref.length number of years (default = 30) preceding (but not including) the index.out timestamp are used as reference period
`agg.na.thres`	threshold for the percentage of na values allowed in the aggregation period data, default = 10
`agg.interpolation`	interpolation type for missing values in individual aggregation period data before applying agg.fun: 'none' (default, NA's are removed), 'linear', 'mean', or 'zeros'

This function determines the dates in each of the aggregation periods for standardized index calculation, extracts the corresponding data from ref.data and applies an aggregation function to the data of each individual aggregation period (default is 'sum', but any function on x can be passed). Reference periods are set by using the ref.years argument to pass specific years to be used as reference period (e.g. for 1981 to 2010, pass seq(1981,2010)). When ref.years is set to NULL, all possible years in ref.data are used. Alternatively, ref.years can be set to NA, in which case ref.length (default = 30) will determine the length of the reference period preceding, but not including, the date for which the reference values are being determined. Warnings will be generated when the requested reference period falls outside ref.data, or when expected aggregation period dates are not present in ref.data.

A named vector with reference period data.

standardized.index, codefit.distribution

data(Ukkel_RR)
date <- as.Date('2018-07-01')
# get all reference values for the 30 day-period preceding date
get.reference.values(date = date, ref.data = Ukkel_RR, agg.length=30)
# get 1981-2010 reference values for the 30 day-period preceding date
get.reference.values(date = date, ref.data = Ukkel_RR, agg.length=30, ref.years=seq(1981,2010))
# get the previos 30 years' reference values for the 30 day-period preceding date
get.reference.values(date = date, ref.data = Ukkel_RR, agg.length=30, ref.years=NA, ref.length=30)