Define a filter for the eBird Basic Dataset (EBD) based on the duration of the checklist. This function only defines the filter and, once all filters have been defined, auk_filter() should be used to call AWK and perform the filtering. Note that checklists with no effort, such as incidental observations, will be excluded if this filter is used since they have no associated duration information.

auk_duration(x, duration)

Arguments

x

auk_ebd or auk_sampling object; reference to file created by auk_ebd() or auk_sampling().

duration

integer; 2 element vector specifying the range of durations in minutes to filter by.

Value

An auk_ebd object.

Details

This function can also work with on an auk_sampling object if the user only wishes to filter the sampling event data.

Examples

# only keep checklists that are less than an hour long
system.file("extdata/ebd-sample.txt", package = "auk") %>%
  auk_ebd() %>%
  auk_duration(duration = c(0, 60))
#> Input 
#>   EBD: /private/var/folders/mg/qh40qmqd7376xn8qxd6hm5lwjyy0h2/T/Rtmp8EzicT/temp_libpathab30c316bf3/auk/extdata/ebd-sample.txt 
#> 
#> Output 
#>   Filters not executed
#> 
#> Filters 
#>   Species: all
#>   Countries: all
#>   States: all
#>   Counties: all
#>   BCRs: all
#>   Bounding box: full extent
#>   Years: all
#>   Date: all
#>   Start time: all
#>   Last edited date: all
#>   Protocol: all
#>   Project code: all
#>   Duration: 0-60 minutes
#>   Distance travelled: all
#>   Records with breeding codes only: no
#>   Exotic Codes: all
#>   Complete checklists only: no
  
# alternatively, without pipes
ebd <- auk_ebd(system.file("extdata/ebd-sample.txt", package = "auk"))
auk_duration(ebd, duration = c(0, 60))
#> Input 
#>   EBD: /private/var/folders/mg/qh40qmqd7376xn8qxd6hm5lwjyy0h2/T/Rtmp8EzicT/temp_libpathab30c316bf3/auk/extdata/ebd-sample.txt 
#> 
#> Output 
#>   Filters not executed
#> 
#> Filters 
#>   Species: all
#>   Countries: all
#>   States: all
#>   Counties: all
#>   BCRs: all
#>   Bounding box: full extent
#>   Years: all
#>   Date: all
#>   Start time: all
#>   Last edited date: all
#>   Protocol: all
#>   Project code: all
#>   Duration: 0-60 minutes
#>   Distance travelled: all
#>   Records with breeding codes only: no
#>   Exotic Codes: all
#>   Complete checklists only: no