Class: Money::Allocation

Inherits:
Object
  • Object
show all
Defined in:
lib/money/money/allocation.rb

Class Method Summary collapse

Class Method Details

.generate(amount, parts, whole_amounts = true) ⇒ Object

Splits a given amount in parts without loosing pennies. The left-over pennies will be distributed round-robin amongst the parties. This means that parties listed first will likely receive more pennies than ones that are listed later.

The results should always add up to the original amount.

The parts can be specified as:

Numeric

Raises:

  • (ArgumentError) 


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# File 'lib/money/money/allocation.rb', line 15

def self.generate(amount, parts, whole_amounts = true)
  parts = parts.is_a?(Numeric) ? Array.new(parts, 1) : parts.dup

  raise ArgumentError, 'need at least one party' if parts.empty?

  result = []
  remaining_amount = amount

  until parts.empty? do
    parts_sum = parts.inject(0, :+)
    part = parts.pop

    current_split = remaining_amount * part / parts_sum
    current_split = current_split.truncate if whole_amounts

    result.unshift current_split
    remaining_amount -= current_split
  end

  result
end