Number::Format - Perl extension for formatting numbers

use Number::Format; my $x = new Number::Format %args; $formatted = $x->round($number, $precision); $formatted = $x->format_number($number, $precision, $trailing_zeroes); $formatted = $x->format_negative($number, $picture); $formatted = $x->format_picture($number, $picture); $formatted = $x->format_price($number, $precision); $formatted = $x->format_bytes($number, $precision); $number = $x->unformat_number($formatted); use Number::Format qw(:subs); $formatted = round($number, $precision); $formatted = format_number($number, $precision, $trailing_zeroes); $formatted = format_negative($number, $picture); $formatted = format_picture($number, $picture); $formatted = format_price($number, $precision); $formatted = format_bytes($number, $precision); $number = unformat_number($formatted);

Perl, version 5.003 or higher.

POSIX.pm will be used if present to determine locale settings.

Carp.pm is used for some error reporting.

These functions provide an easy means of formatting numbers in a manner suitable for displaying to the user.

There are two ways to use this package. One is to declare an object of type Number::Format, which you can think of as a formatting engine. The various functions defined here are provided as object methods. 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 - suffix to add when format_bytes formats megabytes

They may be specified in upper or lower case, with or without a leading hyphen ( - ).

The defaults for `THOUSANDS_SEP`

, `DECIMAL_POINT`

,
`MON_THOUSANDS_SEP`

, `MON_DECIMAL_POINT`

, and `INT_CURR_SYMBOL`

come from the POSIX locale information (see *perllocale*), if available. If your POSIX locale does not provide `MON_THOUSANDS_SEP`

and/or `MON_DECIMAL_POINT`

fields, then the `THOUSANDS_SEP`

and/or
`DECIMAL_POINT`

values are used for those parameters. Some systems (e.g. Win32 ports of
Perl) do not include POSIX support. In those systems, the POSIX system is
bypassed.

If any of the above parameters are not specified when you invoke
new(), then the values are taken from package global variables of the same name
(e.g. `$DECIMAL_POINT`

is the default for the
`DECIMAL_POINT`

parameter). If you use the `:vars`

keyword on your
`use Number::Format`

line (see non-object-oriented example below) you will import those
variables into your namesapce and can assign values as if they were your
own local variables. 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'

Note however that when you first call one of the functions in this module *without* using the object-oriented interface, further setting of those global
variables will have no effect on non-OO calls. It is recommended that you
use the object-oriented interface instead for fewer headaches and a cleaner
design.

The `DECIMAL_FILL`

and `DECIMAL_DIGITS`

values are not set by the Locale system, but are definable by the user.
They 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`

and `MEGA_SUFFIX`

are used by format_bytes() when the value is over 1024 or 1024*1024, respectively. The default values
are ``K'' and ``M''.

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:

use Number::Format; my $de = new Number::Format(-thousands_sep => '.', -decimal_point => ',', -int_curr_symbol => 'DEM'); my $formatted = $de->format_number($number);

Or, if you prefer not to use the object oriented interface, you can do this instead:

use Number::Format qw(:subs :vars); $THOUSANDS_SEP = '.'; $DECIMAL_POINT = ','; $INT_CURR_SYMBOL = 'DEM'; my $formatted = format_number($number);

Nothing is exported by default. To export the functions or the global
variables defined herein, specify the function `name(s)`

on the
import list of the `use Number::Format`

statement. To export all functions defined herein, use the special tag `:subs`

. To export the variables, use the special tag `:vars`

; to export both subs and vars you can use the tag `:all`

.

**new( %args )**-
Creates a new Number::Format object. Valid keys for

`%args`

are any of the parameters described above. Keys may be in all uppercase or all lowercase, and may optionally be preceded by a hyphen (-) character. Example:my $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 (not zero, undef, or the empty string). 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`

. **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 ``K'' appended to the end; or if it is over 1048576 (1024*1024), it will be divided by 1048576 and ``M'' 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`

or`MEGA_SUFFIX`

characters, then the number returned will be multiplied by 1024 or 1024*1024 as appropriate.

William R. Ward, wrw@bayview.com

`perl(1).`