read_xpt: Read and write SAS transport files

Description

The SAS transport format is a open format, as is required for submission of the data to the FDA.

Usage

read_xpt(
  file,
  col_select = NULL,
  skip = 0,
  n_max = Inf,
  .name_repair = "unique"
)
write_xpt(data, path, version = 8, name = NULL)

Arguments

file

Either a path to a file, a connection, or literal data (either a single string or a raw vector).

Files ending in .gz, .bz2, .xz, or .zip will be automatically uncompressed. Files starting with http://, https://, ftp://, or ftps:// will be automatically downloaded. Remote gz files can also be automatically downloaded and decompressed.

Literal data is most useful for examples and tests. It must contain at least one new line to be recognised as data (instead of a path) or be a vector of greater than length 1.

Using a value of clipboard() will read from the system clipboard.

col_select

One or more selection expressions, like in dplyr::select(). Use c() or list() to use more than one expression. See ?dplyr::select for details on available selection options. Only the specified columns will be read from data_file.

skip

Number of lines to skip before reading data.

n_max

Maximum number of lines to read.

.name_repair

Treatment of problematic column names:

"minimal": No name repair or checks, beyond basic existence,
"unique": Make sure names are unique and not empty,
"check_unique": (default value), no name repair, but check they are unique,
"universal": Make the names unique and syntactic
a function: apply custom name repair (e.g., .name_repair = make.names for names in the style of base R).
A purrr-style anonymous function, see rlang::as_function()

This argument is passed on as repair to vctrs::vec_as_names(). See there for more details on these terms and the strategies used to enforce them.

data

Data frame to write.

path

Path to a file where the data will be written.

version

Version of transport file specification to use: either 5 or 8.

name

Member name to record in file. Defaults to file name sans extension. Must be <= 8 characters for version 5, and <= 32 characters for version 8.

Value

A tibble, data frame variant with nice defaults.

Variable labels are stored in the "label" attribute of each variable. It is not printed on the console, but the RStudio viewer will show it.

write_xpt() returns the input data invisibly.

Examples

Run this code

# NOT RUN {
tmp <- tempfile(fileext = ".xpt")
write_xpt(mtcars, tmp)
read_xpt(tmp)
# }

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