Feather provides binary columnar serialization for data frames.
It is designed to make reading and writing data frames efficient,
and to make sharing data across data analysis languages easy.
read_feather() can read both the Feather Version 1 (V1), a legacy version available starting in 2016,
and the Version 2 (V2), which is the Apache Arrow IPC file format.
read_ipc_file() is an alias of read_feather().
read_feather(file, col_select = NULL, as_data_frame = TRUE, mmap = TRUE)
read_ipc_file(file, col_select = NULL, as_data_frame = TRUE, mmap = TRUE)A character file name or URI, raw vector, an Arrow input stream,
or a FileSystem with path (SubTreeFileSystem).
If a file name or URI, an Arrow InputStream will be opened and
closed when finished. If an input stream is provided, it will be left
open.
A character vector of column names to keep, as in the
"select" argument to data.table::fread(), or a
tidy selection specification
of columns, as used in dplyr::select().
Should the function return a data.frame (default) or
an Arrow Table?
Logical: whether to memory-map the file (default TRUE)
A data.frame if as_data_frame is TRUE (the default), or an
Arrow Table otherwise
FeatherReader and RecordBatchReader for lower-level access to reading Arrow IPC data.
# We recommend the ".arrow" extension for Arrow IPC files (Feather V2).
tf <- tempfile(fileext = ".arrow")
on.exit(unlink(tf))
write_feather(mtcars, tf)
df <- read_feather(tf)
dim(df)
#> [1] 32 11
# Can select columns
df <- read_feather(tf, col_select = starts_with("d"))