Module: ActionView::Helpers::NumberHelper

Included in:
ActionView::Helpers
Defined in:
lib/action_view/helpers/number_helper.rb

Overview

Provides methods for converting numbers into formatted strings. Methods are provided for phone numbers, currency, percentage, precision, positional notation, file size and pretty printing.

Most methods expect a number argument, and will return it unchanged if can’t be converted into a valid number.

Defined Under Namespace

Classes: InvalidNumberError

Constant Summary collapse

DEFAULT_CURRENCY_VALUES = 
{ :format => "%u%n", :negative_format => "-%u%n", :unit => "$", :separator => ".", :delimiter => ",",
:precision => 2, :significant => false, :strip_insignificant_zeros => false }
STORAGE_UNITS = 
[:byte, :kb, :mb, :gb, :tb].freeze
DECIMAL_UNITS = 
{0 => :unit, 1 => :ten, 2 => :hundred, 3 => :thousand, 6 => :million, 9 => :billion, 12 => :trillion, 15 => :quadrillion,
-1 => :deci, -2 => :centi, -3 => :mili, -6 => :micro, -9 => :nano, -12 => :pico, -15 => :femto}.freeze

Instance Method Summary collapse

Instance Method Details

#number_to_currency(number, options = {}) ⇒ Object

Formats a number into a currency string (e.g., $13.65). You can customize the format in the options hash.

Options

  • :locale - Sets the locale to be used for formatting (defaults to current locale).

  • :precision - Sets the level of precision (defaults to 2).

  • :unit - Sets the denomination of the currency (defaults to “$”).

  • :separator - Sets the separator between the units (defaults to “.”).

  • :delimiter - Sets the thousands delimiter (defaults to “,”).

  • :format - Sets the format for non-negative numbers (defaults to “%u%n”). Fields are %u for the currency, and %n for the number.

  • :negative_format - Sets the format for negative numbers (defaults to prepending an hyphen to the formatted number given by :format). Accepts the same fields than :format, except %n is here the absolute value of the number.

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_to_currency(1234567890.50)                    # => $1,234,567,890.50
number_to_currency(1234567890.506)                   # => $1,234,567,890.51
number_to_currency(1234567890.506, :precision => 3)  # => $1,234,567,890.506
number_to_currency(1234567890.506, :locale => :fr)   # => 1 234 567 890,51 €
number_to_currency("123a456")                        # => $123a456

number_to_currency("123a456", :raise => true)        # => InvalidNumberError

number_to_currency(-1234567890.50, :negative_format => "(%u%n)")
# => ($1,234,567,890.50)
number_to_currency(1234567890.50, :unit => "£", :separator => ",", :delimiter => "")
# => £1234567890,50
number_to_currency(1234567890.50, :unit => "£", :separator => ",", :delimiter => "", :format => "%n %u")
# => 1234567890,50 £



134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
 
# File 'lib/action_view/helpers/number_helper.rb', line 134

def number_to_currency(number, options = {})
  return unless number

  options.symbolize_keys!

  defaults  = I18n.translate(:'number.format', :locale => options[:locale], :default => {})
  currency  = I18n.translate(:'number.currency.format', :locale => options[:locale], :default => {})
  currency[:negative_format] ||= "-" + currency[:format] if currency[:format]

  defaults  = DEFAULT_CURRENCY_VALUES.merge(defaults).merge!(currency)
  defaults[:negative_format] = "-" + options[:format] if options[:format]
  options   = defaults.merge!(options)

  unit      = options.delete(:unit)
  format    = options.delete(:format)

  if number.to_f < 0
    format = options.delete(:negative_format)
    number = number.respond_to?("abs") ? number.abs : number.sub(/^-/, '')
  end

  begin
    value = number_with_precision(number, options.merge(:raise => true))
    format.gsub(/%n/, value).gsub(/%u/, unit).html_safe
  rescue InvalidNumberError => e
    if options[:raise]
      raise
    else
      formatted_number = format.gsub(/%n/, e.number).gsub(/%u/, unit)
      e.number.to_s.html_safe? ? formatted_number.html_safe : formatted_number
    end
  end

end

#number_to_human(number, options = {}) ⇒ Object

Pretty prints (formats and approximates) a number in a way it is more readable by humans (eg.: 1200000000 becomes “1.2 Billion”). This is useful for numbers that can get very large (and too hard to read).

See number_to_human_size if you want to print a file size.

You can also define you own unit-quantifier names if you want to use other decimal units (eg.: 1500 becomes “1.5 kilometers”, 0.150 becomes “150 milliliters”, etc). You may define a wide range of unit quantifiers, even fractional ones (centi, deci, mili, etc).

Options

  • :locale - Sets the locale to be used for formatting (defaults to current locale).

  • :precision - Sets the precision of the number (defaults to 3).

  • :significant - If true, precision will be the # of significant_digits. If false, the # of fractional digits (defaults to true)

  • :separator - Sets the separator between the fractional and integer digits (defaults to “.”).

  • :delimiter - Sets the thousands delimiter (defaults to “”).

  • :strip_insignificant_zeros - If true removes insignificant zeros after the decimal separator (defaults to true)

  • :units - A Hash of unit quantifier names. Or a string containing an i18n scope where to find this hash. It might have the following keys:

    • integers: :unit, :ten, *:hundred, :thousand, :million, *:billion, :trillion, *:quadrillion

    • fractionals: :deci, :centi, *:mili, :micro, :nano, *:pico, :femto

  • :format - Sets the format of the output string (defaults to “%n %u”). The field types are:

    • %u - The quantifier (ex.: ‘thousand’)

    • %n - The number

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_to_human(123)                                          # => "123"
number_to_human(1234)                                         # => "1.23 Thousand"
number_to_human(12345)                                        # => "12.3 Thousand"
number_to_human(1234567)                                      # => "1.23 Million"
number_to_human(1234567890)                                   # => "1.23 Billion"
number_to_human(1234567890123)                                # => "1.23 Trillion"
number_to_human(1234567890123456)                             # => "1.23 Quadrillion"
number_to_human(1234567890123456789)                          # => "1230 Quadrillion"
number_to_human(489939, :precision => 2)                      # => "490 Thousand"
number_to_human(489939, :precision => 4)                      # => "489.9 Thousand"
number_to_human(1234567, :precision => 4,
                         :significant => false)               # => "1.2346 Million"
number_to_human(1234567, :precision => 1,
                         :separator => ',',
                         :significant => false)               # => "1,2 Million"

Non-significant zeros after the decimal separator are stripped out by default (set :strip_insignificant_zeros to false to change that):

number_to_human(12345012345, :significant_digits => 6)       # => "12.345 Billion"
number_to_human(500000000, :precision => 5)                  # => "500 Million"

Custom Unit Quantifiers

You can also use your own custom unit quantifiers:

number_to_human(500000, :units => {:unit => "ml", :thousand => "lt"})  # => "500 lt"

If in your I18n locale you have:

distance:
  centi:
    one: "centimeter"
    other: "centimeters"
  unit:
    one: "meter"
    other: "meters"
  thousand:
    one: "kilometer"
    other: "kilometers"
  billion: "gazillion-distance"

Then you could do:

number_to_human(543934, :units => :distance)                              # => "544 kilometers"
number_to_human(54393498, :units => :distance)                            # => "54400 kilometers"
number_to_human(54393498000, :units => :distance)                         # => "54.4 gazillion-distance"
number_to_human(343, :units => :distance, :precision => 1)                # => "300 meters"
number_to_human(1, :units => :distance)                                   # => "1 meter"
number_to_human(0.34, :units => :distance)                                # => "34 centimeters"



553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
 
# File 'lib/action_view/helpers/number_helper.rb', line 553

def number_to_human(number, options = {})
  options.symbolize_keys!

  number = begin
    Float(number)
  rescue ArgumentError, TypeError
    if options[:raise]
      raise InvalidNumberError, number
    else
      return number
    end
  end

  defaults = I18n.translate(:'number.format', :locale => options[:locale], :default => {})
  human    = I18n.translate(:'number.human.format', :locale => options[:locale], :default => {})
  defaults = defaults.merge(human)

  options = options.reverse_merge(defaults)
  #for backwards compatibility with those that didn't add strip_insignificant_zeros to their locale files
  options[:strip_insignificant_zeros] = true if not options.key?(:strip_insignificant_zeros)

  inverted_du = DECIMAL_UNITS.invert

  units = options.delete :units
  unit_exponents = case units
  when Hash
    units
  when String, Symbol
    I18n.translate(:"#{units}", :locale => options[:locale], :raise => true)
  when nil
    I18n.translate(:"number.human.decimal_units.units", :locale => options[:locale], :raise => true)
  else
    raise ArgumentError, ":units must be a Hash or String translation scope."
  end.keys.map{|e_name| inverted_du[e_name] }.sort_by{|e| -e}

  number_exponent = number != 0 ? Math.log10(number.abs).floor : 0
  display_exponent = unit_exponents.find{ |e| number_exponent >= e } || 0
  number  /= 10 ** display_exponent

  unit = case units
  when Hash
    units[DECIMAL_UNITS[display_exponent]]
  when String, Symbol
    I18n.translate(:"#{units}.#{DECIMAL_UNITS[display_exponent]}", :locale => options[:locale], :count => number.to_i)
  else
    I18n.translate(:"number.human.decimal_units.units.#{DECIMAL_UNITS[display_exponent]}", :locale => options[:locale], :count => number.to_i)
  end

  decimal_format = options[:format] || I18n.translate(:'number.human.decimal_units.format', :locale => options[:locale], :default => "%n %u")
  formatted_number = number_with_precision(number, options)
  decimal_format.gsub(/%n/, formatted_number).gsub(/%u/, unit).strip.html_safe
end

#number_to_human_size(number, options = {}) ⇒ Object

Formats the bytes in number into a more understandable representation (e.g., giving it 1500 yields 1.5 KB). This method is useful for reporting file sizes to users. You can customize the format in the options hash.

See number_to_human if you want to pretty-print a generic number.

Options

  • :locale - Sets the locale to be used for formatting (defaults to current locale).

  • :precision - Sets the precision of the number (defaults to 3).

  • :significant - If true, precision will be the # of significant_digits. If false, the # of fractional digits (defaults to true)

  • :separator - Sets the separator between the fractional and integer digits (defaults to “.”).

  • :delimiter - Sets the thousands delimiter (defaults to “”).

  • :strip_insignificant_zeros - If true removes insignificant zeros after the decimal separator (defaults to true)

  • :prefix - If :si formats the number using the SI prefix (defaults to :binary)

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_to_human_size(123)                                          # => 123 Bytes
number_to_human_size(1234)                                         # => 1.21 KB
number_to_human_size(12345)                                        # => 12.1 KB
number_to_human_size(1234567)                                      # => 1.18 MB
number_to_human_size(1234567890)                                   # => 1.15 GB
number_to_human_size(1234567890123)                                # => 1.12 TB
number_to_human_size(1234567, :precision => 2)                     # => 1.2 MB
number_to_human_size(483989, :precision => 2)                      # => 470 KB
number_to_human_size(1234567, :precision => 2, :separator => ',')  # => 1,2 MB

Non-significant zeros after the fractional separator are stripped out by default (set :strip_insignificant_zeros to false to change that):

number_to_human_size(1234567890123, :precision => 5)        # => "1.1229 TB"
number_to_human_size(524288000, :precision => 5)            # => "500 MB"



410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
 
# File 'lib/action_view/helpers/number_helper.rb', line 410

def number_to_human_size(number, options = {})
  options.symbolize_keys!

  number = begin
    Float(number)
  rescue ArgumentError, TypeError
    if options[:raise]
      raise InvalidNumberError, number
    else
      return number
    end
  end

  defaults = I18n.translate(:'number.format', :locale => options[:locale], :default => {})
  human    = I18n.translate(:'number.human.format', :locale => options[:locale], :default => {})
  defaults = defaults.merge(human)

  options = options.reverse_merge(defaults)
  #for backwards compatibility with those that didn't add strip_insignificant_zeros to their locale files
  options[:strip_insignificant_zeros] = true if not options.key?(:strip_insignificant_zeros)

  storage_units_format = I18n.translate(:'number.human.storage_units.format', :locale => options[:locale], :raise => true)

  base = options[:prefix] == :si ? 1000 : 1024

  if number.to_i < base
    unit = I18n.translate(:'number.human.storage_units.units.byte', :locale => options[:locale], :count => number.to_i, :raise => true)
    storage_units_format.gsub(/%n/, number.to_i.to_s).gsub(/%u/, unit).html_safe
  else
    max_exp  = STORAGE_UNITS.size - 1
    exponent = (Math.log(number) / Math.log(base)).to_i # Convert to base
    exponent = max_exp if exponent > max_exp # we need this to avoid overflow for the highest unit
    number  /= base ** exponent

    unit_key = STORAGE_UNITS[exponent]
    unit = I18n.translate(:"number.human.storage_units.units.#{unit_key}", :locale => options[:locale], :count => number, :raise => true)

    formatted_number = number_with_precision(number, options)
    storage_units_format.gsub(/%n/, formatted_number).gsub(/%u/, unit).html_safe
  end
end

#number_to_percentage(number, options = {}) ⇒ Object

Formats a number as a percentage string (e.g., 65%). You can customize the format in the options hash.

Options

  • :locale - Sets the locale to be used for formatting (defaults to current locale).

  • :precision - Sets the precision of the number (defaults to 3).

  • :significant - If true, precision will be the # of significant_digits. If false, the # of fractional digits (defaults to false).

  • :separator - Sets the separator between the fractional and integer digits (defaults to “.”).

  • :delimiter - Sets the thousands delimiter (defaults to “”).

  • :strip_insignificant_zeros - If true removes insignificant zeros after the decimal separator (defaults to false).

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_to_percentage(100)                                        # => 100.000%
number_to_percentage("98")                                       # => 98.000%
number_to_percentage(100, :precision => 0)                       # => 100%
number_to_percentage(1000, :delimiter => '.', :separator => ',') # => 1.000,000%
number_to_percentage(302.24398923423, :precision => 5)           # => 302.24399%
number_to_percentage(1000, :locale => :fr)                       # => 1 000,000%
number_to_percentage("98a")                                      # => 98a%

number_to_percentage("98a", :raise => true)                      # => InvalidNumberError



202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
 
# File 'lib/action_view/helpers/number_helper.rb', line 202

def number_to_percentage(number, options = {})
  return unless number

  options.symbolize_keys!

  defaults   = I18n.translate(:'number.format', :locale => options[:locale], :default => {})
  percentage = I18n.translate(:'number.percentage.format', :locale => options[:locale], :default => {})
  defaults  = defaults.merge(percentage)

  options = options.reverse_merge(defaults)

  begin
    "#{number_with_precision(number, options.merge(:raise => true))}%".html_safe
  rescue InvalidNumberError => e
    if options[:raise]
      raise
    else
      e.number.to_s.html_safe? ? "#{e.number}%".html_safe : "#{e.number}%"
    end
  end
end

#number_to_phone(number, options = {}) ⇒ Object

Formats a number into a US phone number (e.g., (555) 123-9876). You can customize the format in the options hash.

Options

  • :area_code - Adds parentheses around the area code.

  • :delimiter - Specifies the delimiter to use (defaults to “-”).

  • :extension - Specifies an extension to add to the end of the generated number.

  • :country_code - Sets the country code for the phone number.

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_to_phone(5551234)                                           # => 555-1234
number_to_phone("5551234")                                         # => 555-1234
number_to_phone(1235551234)                                        # => 123-555-1234
number_to_phone(1235551234, :area_code => true)                    # => (123) 555-1234
number_to_phone(1235551234, :delimiter => " ")                     # => 123 555 1234
number_to_phone(1235551234, :area_code => true, :extension => 555) # => (123) 555-1234 x 555
number_to_phone(1235551234, :country_code => 1)                    # => +1-123-555-1234
number_to_phone("123a456")                                         # => 123a456

number_to_phone("1234a567", :raise => true)                        # => InvalidNumberError

number_to_phone(1235551234, :country_code => 1, :extension => 1343, :delimiter => ".")
# => +1.123.555.1234 x 1343



62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
 
# File 'lib/action_view/helpers/number_helper.rb', line 62

def number_to_phone(number, options = {})
  return unless number

  begin
    Float(number)
  rescue ArgumentError, TypeError
    raise InvalidNumberError, number
  end if options[:raise]

  number       = number.to_s.strip
  options      = options.symbolize_keys
  area_code    = options[:area_code]
  delimiter    = options[:delimiter] || "-"
  extension    = options[:extension]
  country_code = options[:country_code]

  if area_code
    number.gsub!(/(\d{1,3})(\d{3})(\d{4}$)/,"(\\1) \\2#{delimiter}\\3")
  else
    number.gsub!(/(\d{0,3})(\d{3})(\d{4})$/,"\\1#{delimiter}\\2#{delimiter}\\3")
    number.slice!(0, 1) if number.starts_with?(delimiter) && !delimiter.blank?
  end

  str = []
  str << "+#{country_code}#{delimiter}" unless country_code.blank?
  str << number
  str << " x #{extension}" unless extension.blank?
  ERB::Util.html_escape(str.join)
end

#number_with_delimiter(number, options = {}) ⇒ Object

Formats a number with grouped thousands using delimiter (e.g., 12,324). You can customize the format in the options hash.

Options

  • :locale - Sets the locale to be used for formatting (defaults to current locale).

  • :delimiter - Sets the thousands delimiter (defaults to “,”).

  • :separator - Sets the separator between the fractional and integer digits (defaults to “.”).

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_with_delimiter(12345678)                        # => 12,345,678
number_with_delimiter("123456")                        # => 123,456
number_with_delimiter(12345678.05)                     # => 12,345,678.05
number_with_delimiter(12345678, :delimiter => ".")     # => 12.345.678
number_with_delimiter(12345678, :delimiter => ",")     # => 12,345,678
number_with_delimiter(12345678.05, :separator => " ")  # => 12,345,678 05
number_with_delimiter(12345678.05, :locale => :fr)     # => 12 345 678,05
number_with_delimiter("112a")                          # => 112a
number_with_delimiter(98765432.98, :delimiter => " ", :separator => ",")
# => 98 765 432,98

number_with_delimiter("112a", :raise => true)          # => raise InvalidNumberError



253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
 
# File 'lib/action_view/helpers/number_helper.rb', line 253

def number_with_delimiter(number, options = {})
  options.symbolize_keys!

  begin
    Float(number)
  rescue ArgumentError, TypeError
    if options[:raise]
      raise InvalidNumberError, number
    else
      return number
    end
  end

  defaults = I18n.translate(:'number.format', :locale => options[:locale], :default => {})
  options = options.reverse_merge(defaults)

  parts = number.to_s.to_str.split('.')
  parts[0].gsub!(/(\d)(?=(\d\d\d)+(?!\d))/, "\\1#{options[:delimiter]}")
  parts.join(options[:separator]).html_safe

end

#number_with_precision(number, options = {}) ⇒ Object

Formats a number with the specified level of :precision (e.g., 112.32 has a precision of 2 if :significant is false, and 5 if :significant is true). You can customize the format in the options hash.

Options

  • :locale - Sets the locale to be used for formatting (defaults to current locale).

  • :precision - Sets the precision of the number (defaults to 3).

  • :significant - If true, precision will be the # of significant_digits. If false, the # of fractional digits (defaults to false).

  • :separator - Sets the separator between the fractional and integer digits (defaults to “.”).

  • :delimiter - Sets the thousands delimiter (defaults to “”).

  • :strip_insignificant_zeros - If true removes insignificant zeros after the decimal separator (defaults to false).

  • :raise - If true, raises InvalidNumberError when the argument is invalid.

Examples

number_with_precision(111.2345)                                            # => 111.235
number_with_precision(111.2345, :precision => 2)                           # => 111.23
number_with_precision(13, :precision => 5)                                 # => 13.00000
number_with_precision(389.32314, :precision => 0)                          # => 389
number_with_precision(111.2345, :significant => true)                      # => 111
number_with_precision(111.2345, :precision => 1, :significant => true)     # => 100
number_with_precision(13, :precision => 5, :significant => true)           # => 13.000
number_with_precision(111.234, :locale => :fr)                             # => 111,234

number_with_precision(13, :precision => 5, :significant => true, :strip_insignificant_zeros => true)
# => 13

number_with_precision(389.32314, :precision => 4, :significant => true)    # => 389.3
number_with_precision(1111.2345, :precision => 2, :separator => ',', :delimiter => '.')
# => 1.111,23



316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
 
# File 'lib/action_view/helpers/number_helper.rb', line 316

def number_with_precision(number, options = {})
  options.symbolize_keys!

  number = begin
    Float(number)
  rescue ArgumentError, TypeError
    if options[:raise]
      raise InvalidNumberError, number
    else
      return number
    end
  end

  defaults           = I18n.translate(:'number.format', :locale => options[:locale], :default => {})
  precision_defaults = I18n.translate(:'number.precision.format', :locale => options[:locale], :default => {})
  defaults           = defaults.merge(precision_defaults)

  options = options.reverse_merge(defaults)  # Allow the user to unset default values: Eg.: :significant => false
  precision = options.delete :precision
  significant = options.delete :significant
  strip_insignificant_zeros = options.delete :strip_insignificant_zeros

  if significant and precision > 0
    if number == 0
      digits, rounded_number = 1, 0
    else
      digits = (Math.log10(number.abs) + 1).floor
      rounded_number = (BigDecimal.new(number.to_s) / BigDecimal.new((10 ** (digits - precision)).to_f.to_s)).round.to_f * 10 ** (digits - precision)
      digits = (Math.log10(rounded_number.abs) + 1).floor # After rounding, the number of digits may have changed
    end
    precision -= digits
    precision = precision > 0 ? precision : 0  #don't let it be negative
  else
    rounded_number = BigDecimal.new(number.to_s).round(precision).to_f
  end
  formatted_number = number_with_delimiter("%01.#{precision}f" % rounded_number, options)
  if strip_insignificant_zeros
    escaped_separator = Regexp.escape(options[:separator])
    formatted_number.sub(/(#{escaped_separator})(\d*[1-9])?0+\z/, '\1\2').sub(/#{escaped_separator}\z/, '').html_safe
  else
    formatted_number
  end

end