Utility functions for input validity.

Utility function that checks whether a user input is a list of or itself a single valid delay object. This means the user input can be a list in which each element can be one of the following:

• a probability distribution vector: a numeric vector with no NA or negative values, whose entries sum up to 1

• an empirical delay data: a data frame with two columns: event_date and report_delay. The columns cannot contain NA values. report_delay only contains non-negative values

• a delay distribution matrix (as described in .check_is_delay_distribution_matrix)

• a distribution object (e.g. list(name = 'gamma', scale = X, shape = Y))

Or the user input can itself be one of these types.

.is_valid_delay_single_or_list(
  delay_list,
  parameter_name,
  incidence_data_length
)

Arguments

delay_list	user inputted object to be tested
parameter_name	A string containing the name the tested parameter had in the initial function in which it was passed.
incidence_data_length	A number representing the length of the given incidence data.

Value

TRUE if all tests were passed. Throws an error otherwise.