remove_no_date_characters: Remove unnecessary characters from date-like strings

In datetoiso: Convert and Impute Dates to ISO Standard ("International Organization for Standardization")

Remove unnecessary characters from date-like strings

Description

This function cleans a character vector or data frame column containing date-like strings by removing all characters that are not needed for parsing or recognizing dates. It preserves:

• Digits (0–9)

• Letters that appear in any full month name (e.g., "January" → "J, A, N, U, R, Y")

• Selected extra allowed characters: space (" "), dash ("-"), slash ("/"), and "k"/"K"

All other characters (symbols, punctuation, letters not in month names) are removed.

Usage

remove_no_date_characters(df_column)

Arguments

df_column

A character vector (or data frame column) containing date-like strings. Factors will be coerced to character. NA values are preserved.

Details

The function works as follows:

1. Converts input to character vector.

2. Generates the set of letters present in all English month names (case-insensitive).

3. Constructs a regex pattern to match all characters that are NOT digits, allowed letters, or allowed extra symbols.

4. Uses stringr::str_replace_all() to remove unwanted characters.

Value

A character vector of the same length as df_column, with unwanted characters removed. Only digits, letters from month names, and selected extra characters are kept.

Author(s)

Lukasz Andrzejewski

datetoiso documentation built on Dec. 7, 2025, 9:06 a.m.