gasfluxes (version 0.4)

agg.fluxes: Accumulation of fluxes

Description

Aggregate a time series of fluxes to a cummulative flux value.

Usage

agg.fluxes(fluxes, datetimes, timeunit = "hours")

Arguments

fluxes

flux values

datetimes

datetime values (POSIXct or POSIXlt)

timeunit

the unit of time (denominator of the flux unit), supported are the explicit units supported by difftime

Value

A one-row data.frame with columns

flux

the cumulative flux

from

the start of the cumulation period

to

the end of the cumulation period

The return value being a data.frame is useful, when the function is used for "split-apply-combine" type operations to calculate groupwise cumulated values, e.g., using package data.table.

Details

The function uses linear interpolation. The unit of the cumulative flux is [fluxes] * timeunit. NA values are removed and values sorted according to time order. If less then two non-NA value pairs are provided, NA is returned for the cumlative flux.

Examples

# NOT RUN {
#Some random example data
datetimes <- Sys.time() + (1:20)/2*24*3600
set.seed(42)
fluxes <- rlnorm(20, 5)
agg.fluxes(fluxes, datetimes)

# }