class TaskJuggler::RealFormat

This class provides the functionality to format a Float according to certain rules. These rules determine how negative values are represented, how the fractional part is shown and how to structure the mantissa. The result is always a String.

The class uses the following parameters to control the formating. signPrefix: Prefix used for negative numbers. (String) signSuffix: Suffix used for negative numbers. (String) thousandsSeparator: Separator used after 3 integer digits. (String) fractionSeparator: Separator used between the inter part and the

fractional part. (String)

fractionDigits: Number of fractional digits to show. (Integer)

Attributes

fractionDigits[R]

fractionSeparator[R]

signPrefix[R]

signSuffix[R]

thousandsSeparator[R]

Public Class Methods

new(args) click to toggle source

Create a new RealFormat object and define the formating rules.

# File lib/taskjuggler/RealFormat.rb, line 34
def initialize(args)
  iVars = %w( @signPrefix @signSuffix @thousandsSeparator
              @fractionSeparator @fractionDigits )
  if args.is_a?(RealFormat)
    # The argument is another RealFormat object.
    iVars.each do |iVar|
      instance_variable_set(iVar, args.instance_variable_get(iVar))
    end
  elsif args.length == 5
    # The argument is a list of values.
    args.length.times do |i|
      instance_variable_set(iVars[i], args[i])
    end
  else
    raise RuntimeError, "Bad number of parameters #{args.length}"
  end
end

Public Instance Methods

format(number) click to toggle source

Converts the Float number into a String representation according to the formating rules.

# File lib/taskjuggler/RealFormat.rb, line 54
def format(number)
  # Check for negative number. Continue with the absolute part.
  if number < 0
    negate = true
    number = -number
  else
    negate = false
  end

  # Determine the integer part.
  intNumber = (number * (10 ** @fractionDigits)).round.to_i.to_s
  if intNumber.length <= @fractionDigits
    intNumber = '0' * (@fractionDigits - intNumber.length + 1) + intNumber
  end
  intPart = intNumber[0..-(@fractionDigits + 1)]
  # Determinate the fractional part
  fracPart =
    @fractionDigits > 0 ? @fractionSeparator +
                          intNumber[-(@fractionDigits)..-1] : ''

  if @thousandsSeparator.empty?
    out = intPart
  else
    out = ''
    1.upto(intPart.length) do |i|
      out = intPart[-i, 1] + out
      out = @thousandsSeparator + out if i % 3 == 0 && i < intPart.length
    end
  end
  out += fracPart
  # Now compose the result.
  out = @signPrefix + out + @signSuffix if negate
  out
end

to_s() click to toggle source

# File lib/taskjuggler/RealFormat.rb, line 89
def to_s
  [ @signPrefix, @signSuffix, @thousandsSeparator, @fractionSeparator,
    @fractionDigits ].collect { |s| "\"#{s}\"" }.join(' ')
end