Add missing columns to a data frame

Source: R/add-missing-column.R

This is a convenient way to add one more columns (if not already present) to an existing data frame. It is useful to ensure that all required columns are present in a data frame.

add_missing_column(
  .data,
  ...,
  .before = NULL,
  .after = NULL,
  .name_repair = c("check_unique", "unique", "universal", "minimal")
)

Arguments

.data

Data frame to append to.

...

<dynamic-dots> Name-value pairs, passed on to tibble(). All values must have the same size of .data or size 1.

.before, .after

One-based column index or column name where to add the new columns, default: after last column.

.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.

Value

The original data frame with missing columns added if not already present.

Details

It is wrapper on tibble::add_column() that doesn't error if the column is already present.

Examples

data <- tibble::tibble(x = 1:3, y = 3:1)

tibble::add_column(data, z = -1:1, w = 0)
#> # A tibble: 3 × 4
#>       x     y     z     w
#>   <int> <int> <int> <dbl>
#> 1     1     3    -1     0
#> 2     2     2     0     0
#> 3     3     1     1     0
add_missing_column(data, z = -1:1, .before = "y")
#> # A tibble: 3 × 3
#>       x     z     y
#>   <int> <int> <int>
#> 1     1    -1     3
#> 2     2     0     2
#> 3     3     1     1

# add_column errors if already present
try(tibble::add_column(data, x = 4:6))
#> Error in tibble::add_column(data, x = 4:6) : 
#>   Column name `x` must not be duplicated.
#> Use `.name_repair` to specify repair.
#> Caused by error in `repaired_names()`:
#> ! Names must be unique.
#> ✖ These names are duplicated:
#>   * "x" at locations 1 and 3.

# add_missing_column silently ignores
add_missing_column(data, x = 4:6)
#> # A tibble: 3 × 2
#>       x     y
#>   <int> <int>
#> 1     1     3
#> 2     2     2
#> 3     3     1