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readr (version 0.2.2)

write_delim: Save a data frame to a delimited file.

Description

This is about twice as fast as write.csv, and never writes row names. output_column is a generic method used to coerce columns to suitable output.

Usage

write_delim(x, path, delim = " ", na = "NA", append = FALSE, col_names = !append)
write_csv(x, path, na = "NA", append = FALSE, col_names = !append)
write_tsv(x, path, na = "NA", append = FALSE, col_names = !append)
format_csv(x, na = "NA", append = FALSE, col_names = !append)
format_tsv(x, na = "NA", append = FALSE, col_names = !append)
format_delim(x, delim, na = "NA", append = FALSE, col_names = !append)
output_column(x)

Arguments

x
A data frame to write to disk
path
Path to write to.
delim
Delimiter used to seperate values. Defaults to " ". 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 file does not exist a new file is created.
col_names
Write columns names at the top of the file?

Value

write_* returns in the input x invisibily, format_* returns a string.

Output

Factors are coerced to character. Doubles are coerced to character to take advantage of R's nice output for doubles. POSIXct's are formatted as ISO8601. All columns are encoded as UTF-8. Values are only quoted if needed: if they contain a comma, quote or newline.

Examples

Run this code
tmp <- tempfile()
write_csv(mtcars, tmp)
head(read_csv(tmp))

# format_* is useful for testing and reprexes
cat(format_csv(head(mtcars)))
cat(format_tsv(head(mtcars)))
cat(format_delim(head(mtcars), ";"))

df <- data.frame(x = c(1, 2, NA))
format_csv(df, na = ".")

# Quotes are automatically as needed
df <- data.frame(x = c("a", '"', ",", "\n"))
cat(format_csv(df))

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