Namefuncmethodvalueformat?precision?commas123456789.12345679commas4humanize12345.6789humanize3jpy (yen でも可、precision は意味なし)12345.6789jpy2usd (dollar でも可)12345.6789usd4bytes (bytes_binary の別名)123456789.12345679bytes2bytes_binary123456789.12345679bytes_binary2bytes_decimal123456789.12345679bytes_decimal2