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datawizard (version 0.4.0)

data_addprefix: Rename columns and variable names

Description

Safe and intuitive functions to rename variables or rows in data frames. data_rename() will rename column names, i.e. it facilitates renaming variables data_addprefix() or data_addsuffix() add prefixes or suffixes to column names. data_rename_rows() is a convenient shortcut to add or rename row names of a data frame, but unlike row.names(), its input and output is a data frame, thus, integrating smoothly into a possible pipe-workflow.

Usage

data_addprefix(
  data,
  pattern,
  select = NULL,
  exclude = NULL,
  ignore_case = FALSE,
  ...
)

data_addsuffix( data, pattern, select = NULL, exclude = NULL, ignore_case = FALSE, ... )

data_rename(data, pattern = NULL, replacement = NULL, safe = TRUE, ...)

data_rename_rows(data, rows = NULL)

Arguments

data

A data frame, or an object that can be coerced to a data frame.

pattern

Character vector. For data_rename(), indicates columns that should be selected for renaming. Can be NULL (in which case all columns are selected). For data_addprefix() or data_addsuffix(), a character string, which will be added as prefix or suffix to the column names.

select

Variables that will be included when performing the required tasks. Can be either

  • a variable specified as a literal variable name (e.g., column_name),

  • a string with the variable name (e.g., "column_name"), or a character vector of variable names (e.g., c("col1", "col2", "col3")),

  • a formula with variable names (e.g., ~column_1 + column_2),

  • a vector of positive integers, giving the positions counting from the left (e.g. 1 or c(1, 3, 5)),

  • a vector of negative integers, giving the positions counting from the right (e.g., -1 or -1:-3),

  • or one of the following select-helpers: starts_with(""), ends_with(""), contains(""), a range using : or regex("").

If NULL, selects all columns.

exclude

See select, however, column names matched by the pattern from exclude will be excluded instead of selected. If NULL (the default), excludes no columns.

ignore_case

Logical, if TRUE and when one of the select-helpers or a regular expression is used in select, ignores lower/upper case in the search pattern when matching against variable names.

...

Other arguments passed to or from other functions.

replacement

Character vector. Indicates the new name of the columns selected in pattern. Can be NULL (in which case column are numbered in sequential order). If not NULL, pattern and replacement must be of the same length.

safe

Do not throw error if for instance the variable to be renamed/removed doesn't exist.

rows

Vector of row names.

Value

A modified data frame.

See Also

Examples

Run this code
# NOT RUN {
# Add prefix / suffix to all columns
head(data_addprefix(iris, "NEW_"))
head(data_addsuffix(iris, "_OLD"))

# Rename columns
head(data_rename(iris, "Sepal.Length", "length"))
# data_rename(iris, "FakeCol", "length", safe=FALSE)  # This fails
head(data_rename(iris, "FakeCol", "length")) # This doesn't
head(data_rename(iris, c("Sepal.Length", "Sepal.Width"), c("length", "width")))

# Reset names
head(data_rename(iris, NULL))

# Change all
head(data_rename(iris, paste0("Var", 1:5)))

# }

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