Date filtering for PurpleAir Synoptic objects

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.

get timezone from `startdate` if it is `POSIXct`
use passed in `timezone`

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`.

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])
#> # A tibble: 6 × 4
#>   sensor_index name                      date_created        last_seen          
#>   <chr>        <chr>                     <dttm>              <dttm>             
#> 1 6416         "Mid-Valley Clinic"       2018-01-25 20:08:36 2019-01-19 08:17:23
#> 2 6418         "Okanogan Conservation D… 2018-01-25 20:08:48 2020-11-11 17:41:57
#> 3 6424         "Okanogan Airport"        2018-01-25 20:09:18 2023-06-09 02:59:51
#> 4 6430         "Omak Waste Treatment"    2018-01-25 20:10:12 2021-02-18 21:13:50
#> 5 6432         "Mid Valley Hospital "    2018-01-25 20:10:33 2024-03-02 05:46:31
#> 6 6436         "Hopfer Road"             2018-01-25 20:10:50 2024-03-12 19:45:51

Arguments

Note

See also

Examples