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Select a subset of columns

Source: R/auk-select.R
auk_select.Rd

Select a subset of columns from the eBird Basic Dataset (EBD) or the sampling events file. Subsetting the columns can significantly decrease file size.

Usage

auk_select(x, select, file, sep = "\t", overwrite = FALSE)

Arguments

x

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

select

character; a character vector specifying the names of the columns to select. Columns should be as they appear in the header of the EBD; however, names are not case sensitive and spaces may be replaced by underscores, e.g. "COMMON NAME", "common name", and "common_NAME" are all valid.

file

character; output file.

sep

character; the input field separator, the eBird file is tab separated by default. Must only be a single character and space delimited is not allowed since spaces appear in many of the fields.

overwrite

logical; overwrite output file if it already exists

Value

Invisibly returns the filename of the output file.

See also

Other text: auk_clean(), auk_split()

Examples

if (FALSE) { # \dontrun{
# select a minimal set of columns
out_file <- tempfile()
ebd <- auk_ebd(system.file("extdata/ebd-sample.txt", package = "auk"))
cols <- c("latitude", "longitude",
          "group identifier", "sampling event identifier", 
          "scientific name", "observation count",
          "observer_id")
selected <- auk_select(ebd, select = cols, file = out_file)
str(read_ebd(selected))
} # }