NAME Number.Format - JavaScript library for formatting numbers SYNOPSIS JSAN.use('Number.Format'); nf = new Number.Format(); formatted = nf.round(number, precision); formatted = nf.format_number(number, precision, trailing_zeroes); formatted = nf.format_negative(number, picture); formatted = nf.format_picture(number, picture); formatted = nf.format_price(number, precision); formatted = nf.format_bytes(number, precision); number = nf.unformat_number(formatted); DESCRIPTION These functions provide an easy means of formatting numbers in a manner suitable for displaying to the user. This library is a direct port of the Number::Format perl module written by William R. Ward. To use this library you need to create a Number.Format object, which you can think of as a formatting engine. Then call one of the object methods that are defined below. The constructor "new()" can be used to set the parameters of the formatting engine. Valid parameters are: thousands_sep - character inserted between groups of 3 digits decimal_point - character separating integer and fractional parts mon_thousands_sep - like 'thousands_sep', but used for format_price mon_decimal_point - like 'decimal_point', but used for format_price int_curr_symbol - character(s) denoting currency (see format_price()) decimal_digits - number of digits to the right of dec point (def 2) decimal_fill - boolean; whether to add zeroes to fill out decimal neg_format - format to display negative numbers (def ``-x'') kilo_suffix - suffix to add when format_bytes formats kilobytes mega_suffix - " " " " " " megabytes giga_suffix - " " " " " " gigabytes The default values for all the parameters are: thousands_sep = ',' decimal_point = '.' mon_thousands_sep = ',' mon_decimal_point = '.' int_curr_symbol = 'USD' decimal_digits = 2 decimal_fill = 0 neg_format = '-x' kilo_suffix = 'K' mega_suffix = 'M' giga_suffix = 'G' Once the Number.Format object has been created, you can alter any of the parameters directly, by changing their value in the object. nf = new Number.Format( { kilo_suffix : 'kb' } ); nf.kilo_suffix = 'Kb'; The "decimal_fill" and "decimal_digits" values affect the output of "format_number()". Setting "decimal_digits" is like giving that value as the $precision argument to that function. Setting "decimal_fill" to a true value causes "format_number()" to append zeroes to the right of the decimal digits until the length is the specified number of digits. "neg_format" is only used by "format_negative()" and is a string containing the letter 'x', where that letter will be replaced by a positive representation of the number being passed to that function. "format_number()" and "format_price()" utilize this feature by calling "format_negative()" if the number was less than 0. "kilo_suffix", "mega_suffix", and "giga_suffix" are used by "format_bytes()" when the value is over 1024, 1024*1024, or 1024*1024*1024, respectively. The default values are "K", "M", and "G". Note: we can't do TERA because of integer overflows on 32-bit systems. The only restrictions on "decimal_point" and "thousands_sep" are that they must not be digits, must not be identical, and must each be one character. There are no restrictions on "int_curr_symbol". For example, a German user might include this in their code: de = new Number.Format({thousands_sep : '.', decimal_point : ',', int_curr_symbol : 'DEM'}); formatted = de.format_number(number); METHODS new({ param1 : value1, ... }) Creates a new Number.Format object. Valid keys for the args are any of the parameters described above. Keys must be in all lowercase. Example: de = new Number.Format({thousands_sep : '.', decimal_point : ',', int_curr_symbol : 'DEM'}); round(number, precision) Rounds the number to the specified precision. If "precision" is omitted, the value of the "decimal_digits" parameter is used (default value 2). Both input and output are numeric (the function uses math operators rather than string manipulation to do its job), The value of "precision" may be any integer, positive or negative. Examples: round(3.14159) yields 3.14 round(3.14159, 4) yields 3.1416 round(42.00, 4) yields 42 round(1234, -2) yields 1200 Since this is a mathematical rather than string oriented function, there will be no trailing zeroes to the right of the decimal point, and the "decimal_point" and "thousands_sep" variables are ignored. To format your number using the "decimal_point" and "thousands_sep" variables, use "format_number()" instead. format_number(number, precision, trailing_zeroes) Formats a number by adding "thousands_sep" between each set of 3 digits to the left of the decimal point, substituting "decimal_point" for the decimal point, and rounding to the specified precision using "round()". Note that "precision" is a *maximum* precision specifier; trailing zeroes will only appear in the output if "trailing_zeroes" is provided, or the parameter "decimal_fill" is set, with a value that is true. If "precision" is omitted, the value of the "decimal_digits" parameter (default value of 2) is used. Examples: format_number(12345.6789) yields '12,345.68' format_number(123456.789, 2) yields '123,456.79' format_number(1234567.89, 2) yields '1,234,567.89' format_number(1234567.8, 2) yields '1,234,567.8' format_number(1234567.8, 2, 1) yields '1,234,567.80' format_number(1.23456789, 6) yields '1.234568' Of course the output would have your values of "thousands_sep" and "decimal_point" instead of ',' and '.' respectively. format_negative(number, picture) Formats a negative number. Picture should be a string that contains the letter "x" where the number should be inserted. For example, for standard negative numbers you might use ``"-x"'', while for accounting purposes you might use ``"(x)"''. If the specified number begins with a ``-'' character, that will be removed before formatting, but formatting will occur whether or not the number is negative. format_picture(number, picture) Returns a string based on "picture" with the "#" characters replaced by digits from "number". If the length of the integer part of number is too large to fit, the "#" characters are replaced with asterisks ("*") instead. Examples: format_picture(100.023, 'USD ##,###.##') yields 'USD 100.02' format_picture(1000.23, 'USD ##,###.##') yields 'USD 1,000.23' format_picture(10002.3, 'USD ##,###.##') yields 'USD 10,002.30' format_picture(100023, 'USD ##,###.##') yields 'USD **,***.**' format_picture(1.00023, 'USD #.###,###') yields 'USD 1.002,300' The comma (,) and period (.) you see in the picture examples should match the values of "thousands_sep" and "decimal_point", respectively, for proper operation. However, the "thousands_sep" characters in "picture" need not occur every three digits; the *only* use of that variable by this function is to remove leading commas (see the first example above). There may not be more than one instance of "decimal_point" in "picture". The value of "neg_format" is used to determine how negative numbers are displayed. The result of this is that the output of this function my have unexpected spaces before and/or after the number. This is necessary so that positive and negative numbers are formatted into a space the same size. If you are only using positive numbers and want to avoid this problem, set neg_format to "x". format_price(number, precision) Returns a string containing "number" formatted similarly to "format_number()", except that the decimal portion may have trailing zeroes added to make it be exactly "precision" characters long, and the currency string will be prefixed. If the "int_curr_symbol" attribute of the object is the empty string, no currency will be added. If "precision" is not provided, the default of 2 will be used. Examples: format_price(12.95) yields 'USD 12.95' format_price(12) yields 'USD 12.00' format_price(12, 3) yields '12.000' The third example assumes that "int_curr_symbol" is the empty string. format_bytes(number, precision) Returns a string containing "number" formatted similarly to "format_number()", except that if the number is over 1024, it will be divided by 1024 and "kilo_suffix" appended to the end; or if it is over 1048576 (1024*1024), it will be divided by 1048576 and "mega_suffix" appended to the end; or if it is over 1073741824 (1024*1024*1024), it will be divided by 1073741824 and "giga_suffix" appended to the end. Negative values will result in an error. If "precision" is not provided, the default of 2 will be used. Examples: format_bytes(12.95) yields '12.95' format_bytes(2048) yields '2K' format_bytes(1048576) yields '1M' unformat_number(formatted) Converts a string as returned by "format_number()", "format_price()", or "format_picture()", and returns the corresponding value as a numeric scalar. Returns "undef" if the number does not contain any digits. Examples: unformat_number('USD 12.95') yields 12.95 unformat_number('USD 12.00') yields 12 unformat_number('foobar') yields undef unformat_number('1234-567@.8') yields 1234567.8 The value of "decimal_point" is used to determine where to separate the integer and decimal portions of the input. All other non-digit characters, including but not limited to "int_curr_symbol" and "thousands_sep", are removed. If the number matches the pattern of "neg_format" *or* there is a ``-'' character before any of the digits, then a negative number is returned. If the number ends with the "kilo_suffix", "mega_suffix", or "giga_suffix" characters, then the number returned will be scaled appropriately. ACKNOWLEDGEMENTS This library is a direct port of the Number::Format perl module written by William R. Ward. So the majority of the work was done by William. I merely translated the methods from perl to the equivalent JavaScript code. BUGS No known bugs at this time. Please report any problems to the author. SEE ALSO "JSAN" AUTHOR Cees Hek COPYRIGHT Copyright (c) 2005 William R. Ward. Copyright (c) 2006 Cees Hek. All rights reserved. This module is free software; you can redistribute it and/or modify it under the terms of the Artistic license.