pas_filterDate: Date filtering for PurpleAir Synoptic objects

In MazamaScience/AirSensor2: Process and Display Data from Air Quality Sensors

Date filtering for PurpleAir Synoptic objects

Description

Subsets a pas object by date.

Dates can be anything that is understood by MazamaCoreUtils::parseDatetime() including either of the following recommended formats:

• "YYYYmmdd"

• "YYYY-mm-dd"

Timezone determination precedence assumes that if you are passing in POSIXct values then you know what you are doing.

1. get timezone from startdate if it is POSIXct

2. use passed in timezone

Usage

pas_filterDate(pas = NULL, startdate = NULL, enddate = NULL, timezone = NULL)

Arguments

pas	PurpleAir Synoptic pas object.
startdate	Desired start datetime (ISO 8601).
enddate	Desired end datetime (ISO 8601).
timezone	Optional Olson timezone used to interpret dates.

Note

The incoming pas object must contain the date_created and last_modified fields. The returned pas object will retain sites where startdate <= last_seen && enddate >= pas$date_created.

See Also

pas_filter

Examples

library(AirSensor2)

august_2018 <-
 example_pas_historical %>%
  pas_filterDate(
    startdate = 20180701,
    enddate = 20181101,
    timezone = "America/Los_Angeles"
 )

fields <- c("sensor_index", "name", "date_created", "last_seen")
head(august_2018[,fields])

MazamaScience/AirSensor2 documentation built on June 1, 2025, 7:13 p.m.