R: Check whether string, list or vector is empty

is_empty {sjmisc} | R Documentation

## Check whether string, list or vector is empty

### Description

This function checks whether a string or character vector (of length 1), a list or any vector (numeric, atomic) is empty or not.

### Usage

    is_empty(x, first.only = TRUE)

### Arguments

`x` | String, character vector, list, data.frame or numeric vector or factor.
`first.only` | Logical, if `FALSE` and `x` is a character vector, each element of `x` will be checked if empty. If `TRUE`, only the first element of `x` will be checked.

### Value

Logical, `TRUE` if `x` is a character vector or string and is empty, `TRUE` if `x` is a vector or list and of length 0, `FALSE` otherwise.

### Note

`NULL`- or `NA`-values are also considered as "empty" (see 'Examples') and will return `TRUE`.

### Examples

    is_empty("test")
    is_empty("")
    is_empty(NA)
    is_empty(NULL)

    # string is not empty
    is_empty(" ")

    # however, this trimmed string is
    is_empty(trim(" "))

    # numeric vector
    x <- 1
    is_empty(x)
    x <- x[-1]
    is_empty(x)

    # check multiple elements of character vectors
    is_empty(c("", "a"))
    is_empty(c("", "a"), first.only = FALSE)

    # empty data frame
    d <- data.frame()
    is_empty(d)

[Package sjmisc version 2.7.5 Index]