Class: FinancialCalculator::Ppmt

Inherits:
Object
  • Object
show all
Includes:
Validator
Defined in:
lib/financial_calculator/ppmt.rb

Overview

Calculates the principal portion of a loan or annuity for a particular period

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(rate, period, num_periods, present_value, future_value = 0, pay_at_beginning = false) ⇒ FinancialCalculator::Npv

Create a new object for calculating the periodic payment of an ordinary annuity

Parameters:

  • rate (Numeric) —

    The discount (interest) rate

  • period (Numeric) —

    The amortization period

  • num_periods (Numeric) —

    The number of payments to be made

  • present_value (Numeric) —

    The current value of the annuity

  • future_value (Numeric) (defaults to: 0) —

    The ending value of the annuity

  • pay_at_beginning. (Boolean) —

    Whether the payment is made at the beginning of the period (true) or end of the period (false)



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# File 'lib/financial_calculator/ppmt.rb', line 44

def initialize(rate, period, num_periods, present_value, future_value = 0, pay_at_beginning = false)
  validate_numerics(rate: rate, period: period, num_periods: num_periods, present_value: present_value, future_value: future_value)

  @rate             = Flt::DecNum(rate.to_s)
  @period           = Flt::DecNum(period)
  @num_periods      = Flt::DecNum(num_periods.to_s)
  @present_value    = Flt::DecNum(present_value.to_s)
  @future_value     = Flt::DecNum(future_value.to_s)
  @pay_at_beginning = pay_at_beginning
  @result           = solve(@rate, @period, @num_periods, @present_value, @future_value, @pay_at_beginning)
end

Instance Attribute Details

#future_value ⇒ Numeric (readonly)

Returns The ending value of the annuity. Defaults to 0.

Returns:

  • (Numeric) —

    The ending value of the annuity. Defaults to 0



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# File 'lib/financial_calculator/ppmt.rb', line 24

def future_value
  @future_value
end

#num_periods ⇒ Numeric (readonly)

Returns The number of payments to be made.

Returns:

  • (Numeric) —

    The number of payments to be made



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# File 'lib/financial_calculator/ppmt.rb', line 16

def num_periods
  @num_periods
end

#pay_at_beginning ⇒ Boolean (readonly)

Returns Whether the payment is made at the beginning of the period (true) or end of the period (false).

Returns:

  • (Boolean) —

    Whether the payment is made at the beginning of the period (true) or end of the period (false)



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# File 'lib/financial_calculator/ppmt.rb', line 29

def pay_at_beginning
  @pay_at_beginning
end

#period ⇒ Numeric (readonly)

Returns The amortization period.

Returns:

  • (Numeric) —

    The amortization period



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# File 'lib/financial_calculator/ppmt.rb', line 12

def period
  @period
end

#present_value ⇒ Numeric (readonly)

Returns The current value of the annuity.

Returns:

  • (Numeric) —

    The current value of the annuity



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# File 'lib/financial_calculator/ppmt.rb', line 20

def present_value
  @present_value
end

#rate ⇒ Numeric (readonly)

Returns The rate used for calculating the payment amount.

Returns:

  • (Numeric) —

    The rate used for calculating the payment amount



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# File 'lib/financial_calculator/ppmt.rb', line 8

def rate
  @rate
end

#result ⇒ DecNum (readonly)

Returns Result of the PMT calculation.

Returns:

  • (DecNum) —

    Result of the PMT calculation



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# File 'lib/financial_calculator/ppmt.rb', line 33

def result
  @result
end

Instance Method Details

#inspect ⇒ Object 



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# File 'lib/financial_calculator/ppmt.rb', line 62

def inspect
  "PPMT(#{result})"
end

#pays_at_beginning? ⇒ Boolean

Returns Whether the payments are made at the beginning of each period.

Returns:

  • (Boolean) —

    Whether the payments are made at the beginning of each period



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# File 'lib/financial_calculator/ppmt.rb', line 58

def pays_at_beginning?
  @pay_at_beginning
end