libbib (version 1.6.4)

normalize_isbn_10: Attempt to enforce validity and canonical form to ISBN 10

Description

Takes a string representation of an ISBN 10. Strips all non-digit and non-"X" characters and checks if it is valid (whether the check digit works out, etc). User can specify whether "aggressive" measures should be taken to salvage the malformed ISBN 10 string.

Usage

normalize_isbn_10(x, aggressive = TRUE, convert.to.isbn.13 = FALSE)

Value

Returns valid ISBN 10 if possible, NA if not

Arguments

x

A string

aggressive

A logical indicating whether aggressive measures should be taken to try to get the "ISBN 10" into a valid form. See "Details" for more info (default is TRUE)

convert.to.isbn.13

A logical indicating whether the ISBN 10 should be converted into an ISBN 13 (default is FALSE)

Details

If aggressive is TRUE, aggressive measures are taken to try to salvage the malformed ISBN 10 string. If the ISBN 10, for example, is 9 digits, and either adding an "X" to the end, or leading "0"s fix it, this function will return the salvaged ISBN 10. If the ISBN 10 has garbage digits/characters in the front and has an "X" check digit, it will return the salvaged ISBN 10.

See Also

normalize_isbn normalize_isbn_13

Examples

normalize_isbn_10("012491540x")                    # "012491540X"
normalize_isbn_10("012491540x xe32ea")             # "012491540X"
normalize_isbn_10("012491540x", convert.to.isbn.13=TRUE)
# "9780124915404"
normalize_isbn_10("513213012491540x")              # "012491540X"