readr: write_delim – R documentation

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write_delim

Write a data frame to a delimited file

Description

The write_*() family of functions are an improvement to analogous function such as write.csv() because they are approximately twice as fast. Unlike write.csv(), these functions do not include row names as a column in the written file. A generic function, output_column(), is applied to each variable to coerce columns to suitable output.

Usage

write_delim(
  x,
  file,
  delim = " ",
  na = "NA",
  append = FALSE,
  col_names = !append,
  quote_escape = "double",
  eol = "\n",
  path = deprecated()
)

write_csv(
  x,
  file,
  na = "NA",
  append = FALSE,
  col_names = !append,
  quote_escape = "double",
  eol = "\n",
  path = deprecated()
)

write_csv2(
  x,
  file,
  na = "NA",
  append = FALSE,
  col_names = !append,
  quote_escape = "double",
  eol = "\n",
  path = deprecated()
)

write_excel_csv(
  x,
  file,
  na = "NA",
  append = FALSE,
  col_names = !append,
  delim = ",",
  quote_escape = "double",
  eol = "\n",
  path = deprecated()
)

write_excel_csv2(
  x,
  file,
  na = "NA",
  append = FALSE,
  col_names = !append,
  delim = ";",
  quote_escape = "double",
  eol = "\n",
  path = deprecated()
)

write_tsv(
  x,
  file,
  na = "NA",
  append = FALSE,
  col_names = !append,
  quote_escape = "double",
  eol = "\n",
  path = deprecated()
)

Arguments

`x`	A data frame or tibble to write to disk.
`file`	File or connection to write to.
`delim`	Delimiter used to separate values. Defaults to `" "` for `write_delim()`, `","` for `write_excel_csv()` and `";"` for `write_excel_csv2()`. Must be a single character.
`na`	String used for missing values. Defaults to NA. Missing values will never be quoted; strings with the same value as `na` will always be quoted.
`append`	If `FALSE`, will overwrite existing file. If `TRUE`, will append to existing file. In both cases, if the file does not exist a new file is created.
`col_names`	If `FALSE`, column names will not be included at the top of the file. If `TRUE`, column names will be included. If not specified, `col_names` will take the opposite value given to `append`.
`quote_escape`	The type of escaping to use for quoted values, one of `"double"`, `"backslash"` or `"none"`. You can also use `FALSE`, which is equivalent to "none". The default is `"double"`, which is expected format for Excel.
`eol`	The end of line character to use. Most commonly either `"\n"` for Unix style newlines, or `"\r\n"` for Windows style newlines.
`path`

Value

write_*() returns the input x invisibly.

Output

Factors are coerced to character. Doubles are formatted to a decimal string using the grisu3 algorithm. POSIXct values are formatted as ISO8601 with a UTC timezone Note: POSIXct objects in local or non-UTC timezones will be converted to UTC time before writing.

All columns are encoded as UTF-8. write_excel_csv() and write_excel_csv2() also include a UTF-8 Byte order mark which indicates to Excel the csv is UTF-8 encoded.

write_excel_csv2() and write_csv2 were created to allow users with different locale settings to save .csv files using their default settings (e.g. ; as the column separator and , as the decimal separator). This is common in some European countries.

Values are only quoted if they contain a comma, quote or newline.

The write_*() functions will automatically compress outputs if an appropriate extension is given. Three extensions are currently supported: .gz for gzip compression, .bz2 for bzip2 compression and .xz for lzma compression. See the examples for more information.

References

Florian Loitsch, Printing Floating-Point Numbers Quickly and Accurately with Integers, PLDI '10, http://www.cs.tufts.edu/~nr/cs257/archive/florian-loitsch/printf.pdf

Examples

data(storms, package = "dplyr")
# If only a file name is specified, write_()* will write
# the file to the current working directory.
write_csv(storms, "storms.csv")
write_tsv(storms, "storms.tsv")

# If you add an extension to the file name, write_()* will
# automatically compress the output.
write_tsv(storms, "storms.tsv.gz")
write_tsv(storms, "storms.tsv.bz2")
write_tsv(storms, "storms.tsv.xz")

readr

Read Rectangular Text Data

v1.4.0

GPL (>= 2) | file LICENSE

Authors

Hadley Wickham [aut], Jim Hester [aut, cre], Romain Francois [ctb], R Core Team [ctb] (Date time code adapted from R), RStudio [cph, fnd], Jukka Jylänki [ctb, cph] (grisu3 implementation), Mikkel Jørgensen [ctb, cph] (grisu3 implementation)

Initial release