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Is an Argument a Numeric Vector?

Source: R/assertions.R
assert_numeric_vector.Rd

Checks if an argument is a numeric vector

Usage

assert_numeric_vector(
  arg,
  length = NULL,
  optional = FALSE,
  arg_name = rlang::caller_arg(arg),
  message = NULL,
  class = "assert_numeric_vector",
  call = parent.frame()
)

Arguments

arg

A function argument to be checked

length

Expected length

If the argument is not specified or set to NULL, any length is accepted.

optional

Is the checked argument optional? If set to FALSE and arg is NULL then an error is thrown

arg_name

string indicating the label/symbol of the object being checked.

message

string passed to cli::cli_abort(message). When NULL, default messaging is used (see examples for default messages). "{arg_name}" can be used in messaging.

class

Subclass of the condition.

call

The execution environment of a currently running function, e.g. call = caller_env(). The corresponding function call is retrieved and mentioned in error messages as the source of the error.

You only need to supply call when throwing a condition from a helper function which wouldn't be relevant to mention in the message.

Can also be NULL or a defused function call to respectively not display any call or hard-code a code to display.

For more information about error calls, see Including function calls in error messages.

Value

The function throws an error if arg is not a numeric vector. Otherwise, the input is returned invisibly.

See also

Checks for valid input and returns warning or errors messages: assert_atomic_vector(), assert_character_scalar(), assert_character_vector(), assert_data_frame(), assert_date_vector(), assert_expr(), assert_expr_list(), assert_filter_cond(), assert_function(), assert_integer_scalar(), assert_list_element(), assert_list_of(), assert_logical_scalar(), assert_named(), assert_one_to_one(), assert_param_does_not_exist(), assert_s3_class(), assert_same_type(), assert_symbol(), assert_unit(), assert_vars(), assert_varval_list()

Examples

example_fun <- function(num) {
  assert_numeric_vector(num)
}

example_fun(1:10)

try(example_fun(letters))
#> Error in example_fun(letters) : 
#>   Argument `num` must be a numeric vector, but it is a character vector.

example_fun <- function(num) {
  assert_numeric_vector(num, length = 2)
}

try(example_fun(1:10))
#> Error in example_fun(1:10) : 
#>   Argument `num` must be a vector of length 2, but has length 10.