R: Tools for working with row names

rownames {tibble} | R Documentation

## Tools for working with row names

### Description

While a tibble can have row names (e.g., when converting from a regular data frame), they are removed when subsetting with the `[` operator. A warning will be raised when attempting to assign non-`NULL` row names to a tibble. Generally, it is best to avoid row names, because they are basically a character column with different semantics to every other column. These functions allow to you detect if a data frame has row names (`has_rownames()`), remove them (`remove_rownames()`), or convert them back-and-forth between an explicit column (`rownames_to_column()` and `column_to_rownames()`). Also included is `rowid_to_column()` which adds a column at the start of the dataframe of ascending sequential row ids starting at 1. Note that this will remove any existing row names.

### Usage

    has_rownames(df)

    remove_rownames(df)

    rownames_to_column(df, var = "rowname")

    rowid_to_column(df, var = "rowid")

    column_to_rownames(df, var = "rowname")

### Arguments

`df` | A data frame
`var` | Name of column to use for rownames.

### Details

In the printed output, the presence of row names is indicated by a star just above the row numbers.

### Examples

    has_rownames(mtcars)
    has_rownames(iris)
    has_rownames(remove_rownames(mtcars))

    head(rownames_to_column(mtcars))

    mtcars_tbl <- as_tibble(rownames_to_column(mtcars))
    mtcars_tbl
    column_to_rownames(as.data.frame(mtcars_tbl))

[Package tibble version 1.3.3 Index]