Serialize to newline delimited JSON representation

Source code

Description

Serialize to newline delimited JSON representation

Usage

<DataFrame>$write_ndjson(
  file,
  ...,
  compression = c("uncompressed", "gzip", "zstd"),
  compression_level = NULL,
  check_extension = TRUE
)

Arguments

file	File path to which the result will be written.
…	These dots are for future extensions and must be empty.
compression	What compression format to use. Must be one of uncompressed (default), gzip, or zstd.
compression_level	The compression level to use, typically 0-9 or NULL to let the engine choose.
check_extension	Whether to check if the filename matches the compression settings. Will raise an error if compression is set to “uncompressed” and the filename ends in one of “.gz”, “.zst”, “.zstd”, or if compression != “uncompressed” and the file uses a mismatched extension. Only applies if file is a path.

Value

NULL invisibly.

Examples

library("polars")


dat <- as_polars_df(head(mtcars))
destination <- tempfile()

dat$select(pl$col("drat", "mpg"))$write_ndjson(destination)
jsonlite::stream_in(file(destination))

#> 
 Found 6 records...
 Imported 6 records. Simplifying...

#>   drat  mpg
#> 1 3.90 21.0
#> 2 3.90 21.0
#> 3 3.85 22.8
#> 4 3.08 21.4
#> 5 3.15 18.7
#> 6 2.76 18.1