Import an analysis dataset — import

Read common tabular data formats through one consistent interface. Optional packages are required only for the formats that use them.

Usage

import_data(
  file,
  format = NULL,
  sheet = NULL,
  header = TRUE,
  sep = NULL,
  na = c("", "NA"),
  encoding = "UTF-8",
  name_repair = c("check_unique", "unique", "minimal"),
  ...
)

Arguments

file: Path to the data file.
format: Optional file format when it cannot be inferred from `file`. Supply an extension without the leading dot, such as `"csv"` or `"dta"`.
sheet: Excel sheet name or number. Used only for `.xls` and `.xlsx` files. The first sheet is used by default.
header: Logical; whether delimited text files contain column names.
sep: Optional delimiter for `.csv`, `.tsv`, and `.txt` files. Defaults to comma for CSV, tab for TSV, and whitespace for TXT.
na: Character vector of strings interpreted as missing values.
encoding: Character encoding used for delimited text files. With the default "UTF-8", a file that is not valid UTF-8 (typically a Latin-1 or Windows-1252 export) is read as Latin-1 and a message says so; set encoding explicitly to override.
name_repair: How to handle column names: `"check_unique"` preserves names and errors on blank or duplicated names; `"unique"` repairs them with [make.names()]; `"minimal"` preserves names without checking.
...: Additional arguments passed to the format-specific reader.

Value

A data frame. Tibbles and labelled columns returned by `readxl` or `haven` are retained.

Details

Supported extensions are CSV (`.csv`), tab-separated or text files (`.tsv`, `.txt`), Excel (`.xls`, `.xlsx`), R data (`.rds`), Stata (`.dta`), SPSS (`.sav`, `.zsav`, `.por`), and SAS (`.sas7bdat`, `.xpt`).

`readxl` is required for Excel files and `haven` is required for Stata, SPSS, and SAS files. RDS files must contain a data frame or tibble.

Examples

csv_file <- tempfile(fileext = ".csv")
utils::write.csv(
  data.frame(outcome = c(0, 1), age = c(45, 61)),
  csv_file,
  row.names = FALSE
)
imported <- import_data(csv_file)
names(imported)
#> [1] "outcome" "age"