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Write a list of data frames to CSV and keep it movin'

Source: R/batch_csv_dump.R
batch_csv_dump.Rd

This function takes either a list of data frames, or a data frame and a column to split by, and writes them all to CSV files. It then returns the list of data frames, optionally row-binded back together. It fits neatly in the middle of a longer piped workflow.

Usage

batch_csv_dump(
  data,
  split_by,
  path = ".",
  base_name = NULL,
  bind = FALSE,
  verbose = TRUE,
  ...
)

Arguments

data

A data frame or a list of data frames

split_by

Bare column name of variable to split by. If data is a list, this is unnecessary and will be ignored.

path

String giving a path at which to save files; defaults to current working directory.

base_name

Optional string to be prepended to all file names.

bind

Logical: whether to row-bind list of data frames into a single data frame. Defaults FALSE, in which case a list of data frames is returned.

verbose

Logical: whether to print files' paths and names as they're written. Defaults TRUE.

...

Arguments passed on to utils::write.table

append

logical. Only relevant if file is a character string. If TRUE, the output is appended to the file. If FALSE, any existing file of the name is destroyed.

quote

a logical value (TRUE or FALSE) or a numeric vector. If TRUE, any character or factor columns will be surrounded by double quotes. If a numeric vector, its elements are taken as the indices of columns to quote. In both cases, row and column names are quoted if they are written. If FALSE, nothing is quoted.

eol

the character(s) to print at the end of each line (row). For example, eol = "\r\n" will produce Windows' line endings on a Unix-alike OS, and eol = "\r" will produce files as expected by Excel:mac 2004.

na

the string to use for missing values in the data.

dec

the string to use for decimal points in numeric or complex columns: must be a single character.

col.names

either a logical value indicating whether the column names of x are to be written along with x, or a character vector of column names to be written. See the section on ‘CSV files’ for the meaning of col.names = NA.

qmethod

a character string specifying how to deal with embedded double quote characters when quoting strings. Must be one of "escape" (default for write.table), in which case the quote character is escaped in C style by a backslash, or "double" (default for write.csv and write.csv2), in which case it is doubled. You can specify just the initial letter.

fileEncoding

character string: if non-empty declares the encoding to be used on a file (not a connection) so the character data can be re-encoded as they are written. See file.

Value

Either a list of data frames (in case of bind = FALSE) or a single data frame (in case of bind = TRUE).