csv_read_options function

CSV Reading Options

csv_read_options(
  use_threads = option_use_threads(),
  block_size = 1048576L,
  skip_rows = 0L,
  column_names = character(0),
  autogenerate_column_names = FALSE,
  encoding = "UTF-8",
  skip_rows_after_names = 0L
)

Arguments

• use_threads: Whether to use the global CPU thread pool
• block_size: Block size we request from the IO layer; also determines the size of chunks when use_threads is TRUE.
• skip_rows: Number of lines to skip before reading data (default 0).
• column_names: Character vector to supply column names. If length-0 (the default), the first non-skipped row will be parsed to generate column names, unless autogenerate_column_names is TRUE.
• autogenerate_column_names: Logical: generate column names instead of using the first non-skipped row (the default)? If TRUE, column names will be "f0", "f1", ..., "fN".
• encoding: The file encoding. (default "UTF-8")
• skip_rows_after_names: Number of lines to skip after the column names (default 0). This number can be larger than the number of rows in one block, and empty rows are counted. The order of application is as follows: - skip_rows is applied (if non-zero); - column names are read (unless column_names is set); - skip_rows_after_names is applied (if non-zero).

Examples

tf <- tempfile()
on.exit(unlink(tf))
writeLines("my file has a non-data header\nx\n1\n2", tf)
read_csv_arrow(tf, read_options = csv_read_options(skip_rows = 1))
open_csv_dataset(tf, read_options = csv_read_options(skip_rows = 1))