rollingSum: apply aggregating functions to contiguous stretches of data

In delftfews: delftfews R extensions

Description

'rollingSum' is a commodity function invoking 'zoo::rollapply' with 'FUN=sum'.

'rollapply.delftfews' overrides 'rollapply.zoo' defaults for 'na.pad' (set to TRUE) and ‘align' (set to ’right'). this can also be done by changing global settings at the moment you load the library.

Usage

rollingSum(data, width, na.action=na.zero)

Arguments

data	the input data vector with instantaneous values
width	the number of values of the sum.
na.action	what to do with NA values.

Examples

# on this input
input <- c(rep(1:3, 2), NA)
# [1]  1  2  3  1  2  3 NA

# this sums the two elements [i-1, i]
rollingSum(input, 2)
# [1] NA  3  5  4  3  5  3

# the three elements [i-2, i-1, i]
rollingSum(input, 3)
# [1] NA NA  6  6  6  6  5

rollingSum(input, 4)
# notice how the first `width - 1` elements in the result are NA
# [1] NA NA NA  7  8  9  6

delftfews documentation built on May 2, 2019, 4:48 p.m.