durations: Calculate duration of data in each group

In LightLogR: Process Data from Wearable Light Loggers and Optical Radiation Dosimeters

Calculate duration of data in each group

Description

This function calculates the total duration of data in each group of a dataset, based on a datetime column and a variable column. It uses the dominant epoch (interval) of each group to calculate the duration.

Usage

durations(
  dataset,
  Variable.colname = Datetime,
  Datetime.colname = Datetime,
  count.NA = FALSE,
  show.missing = FALSE,
  show.interval = FALSE,
  FALSE.as.NA = FALSE
)

Arguments

dataset	A light logger dataset. Expects a dataframe. If not imported by LightLogR, take care to choose sensible variables for the Datetime.colname and Variable.colname.
Variable.colname	Column name that contains the variable for which to calculate the duration. Expects a symbol. Needs to be part of the dataset.
Datetime.colname	Column name that contains the datetime. Defaults to "Datetime" which is automatically correct for data imported with LightLogR. Expects a symbol. Needs to be part of the dataset. Must be of type POSIXct.
count.NA	Logical. Should NA values in Variable.colname be counted as part of the duration? Defaults to FALSE.
show.missing	Logical. Should the duration of NAs be provided in a separate column "Missing"? Defaults to FALSE.
show.interval	Logical. Should the dominant epoch (interval) be shown in a column "interval"? Defaults to FALSE.
FALSE.as.NA	Logical. Should FALSE values in the Variable.colname be treated as NA (i.e., missing)?

Value

A tibble with one row per group and a column "duration" containing the duration of each group as a lubridate::duration(). If show.missing = TRUE, a column "missing" is added with the duration of NAs, and a column "total" with the total duration. If show.interval = TRUE, a column "interval" is added with the dominant epoch of each group.

Examples

# Calculate the duration of a dataset
durations(sample.data.environment)

# create artificial gaps in the data
gapped_data <-
sample.data.environment |>
  dplyr::filter(MEDI >= 10) |>
  gap_handler(full.days = TRUE)

#by default, the Datetime column is selected for the `Variable.colname`, 
#basically ignoring NA measurement values
gapped_data |>
 durations(count.NA = TRUE)

# Calculate the duration where MEDI are available
durations(gapped_data, MEDI)

# Calculate the duration, show the duration of NAs separately
durations(gapped_data, MEDI, show.missing = TRUE)

# Calculate the duration, show the dominant epoch
durations(gapped_data, Variable.colname = MEDI, show.interval = TRUE)

# Calculate durations for day and night separately
gapped_data |>
  add_photoperiod(coordinates = c(48.52, 9.06)) |>
  dplyr::group_by(photoperiod.state, .add = TRUE) |>
  durations(Variable.colname = MEDI, show.interval = TRUE, show.missing = TRUE)

LightLogR documentation built on June 10, 2025, 5:12 p.m.