README.md

In Alipsa/financials: Financial functions

financials

R package for financial functions for the Renjin implementation of R for the JVM.

To use it add the following dependency to your pom

<dependency>
    <groupId>se.alipsa</groupId>
    <artifactId>financials</artifactId>
    <version>1.0.0</version>
</dependency>

Functions

Payment

pmt <- function(interestRate, nper, pv, fv = 0, type = 0)

Equivalent to Excel/Calc's PMT(interest_rate, number_payments, PV, FV, Type) function, which calculates the payments for a loan or the future value of an investment

Parameters

• interestRate periodic interest rate represented as a decimal.
• nper number of total payments / periods.
• pv present value -- borrowed or invested principal.
• fv future value of loan or annuity, default to 0 (which is what you want for loans)
• type when payment is made: beginning of period is 1; end is 0. Default is 0

Value

returns A double representing the periodic payment amount.

Example

Calulate payment for a loan

The following data:

| Item | amount | | ----- | ----- | | Loan Amount | 50000 | | Interest rate | 3.50% | | Periods | 60 | | Monthly payment | 909.59 |

Then the Monthly payment can be calculated as pmt(3.5/100/12, 60, -50000)

Monthly Annuity Amount

monthlyAnnuityAmount <- function(loanAmount, interestRate, tenureMonths, amortizationFreemonths = 0, type = 0)

Calculate the monthly annuity amount i.e. the amortization and interest amount each payment period (month)

Parameters

• loanAmount the total loan amount including capitalized fees (e.g. startup fee)
• interestRate the annual nominal interest
• tenureMonths the tenure of the loan in number of months
• amortizationFreeMonths the number of initial amortization free months, default to 0
• type - when payment is made: beginning of period is 1; end is 0. Default is 0

Value

returns the monthly annuity amount

Example

Assuming the following:

| Item | amount | | ----- | ----- | | Loan Amount | 50000 | | Interest rate | 3.50% | | Tenure | 60 | | Amortization Free months | 6 |

The monthly annuity amount would be monthlyAnnuityAmount(50000, 3.5/100, 60, 6) = 1002.10

Cash Flow

cashFlow <- function(loanAmount, interestRate, tenureMonths, amortizationFreeMonths, invoiceFee)

Parameters

• loanAmount the total loan amount including capitalized fees (e.g. startup fee)
• interestRate the annual nominal interest
• tenureMonths the tenure of the loan in number of months
• amortizationFreeMonths the number of initial amortization free months, default to 0
• invoiceFee a fee for each statement invoiced, default to 0

Value

returns a vector of cachFlow entries for each period

Example

cf <- cashFlow(
  loanAmount=50000,
  interestRate=0.035,
  tenureMonths=60,
  amortizationFreeMonths=6,
  invoiceFee=30
)

Payment Plan

paymentPlan <- function(loanAmount, interestRate, tenureMonths, amortizationFreeMonths = 0, invoiceFee = 0)

Parameters

• loanAmount the total loan amount including capitalized fees (e.g. startup fee)
• interestRate the annual nominal interest
• tenureMonths the total tenure of the loan in number of months
• amortizationFreeMonths the number of initial amortization free months, default to 0
• invoiceFee a fee for each statement invoiced, default to 0

Value

returns a dataframe with the initial payment plan based on the input, based on monthly payment periods

Example

loanAmt <- 10000
tenureMonths <- 1.5 * 12
amortizationFreeMonths <- 6
interest <- 3.5 / 100
invoiceFee <- 30

ppdf <- paymentPlan(loanAmt, interest, tenureMonths, amortizationFreeMonths, invoiceFee)

which will yield a data.frame (ppdf) as follows:

| month | costOfCredit | interestAmt | amortization | invoiceFee | outgoingBalance | cashFlow | | ---- | -------- | ------ | ------ | ------ | ------ | ---- | | 0 | 0 | 0 | 0 | 0 | 10000 | -10000 | | 1 | 29.167 | 29.167 | 0 | 30 | 10000 | 59.167 | | 2 | 29.167 | 29.167 | 0 | 30 | 10000 | 59.167 | | 3 | 29.167 | 29.167 | 0 | 30 | 10000 | 59.167 | | 4 | 29.167 | 29.167 | 0 | 30 | 10000 | 59.167 | | 5 | 29.167 | 29.167 | 0 | 30 | 10000 | 59.167 | | 6 | 849.216 | 29.167 | 820.05 | 30 | 9179.95 | 879.216 | | 7 | 849.216 | 26.775 | 822.441 | 30 | 8357.509 | 879.216 | | 8 | 849.216 | 24.376 | 824.84 | 30 | 7532.669 | 879.216 | | 9 | 849.216 | 21.97 | 827.246 | 30 | 6705.423 | 879.216 | |10 | 849.216 | 19.557 | 829.659 | 30 | 5875.764 | 879.216 | |11 | 849.216 | 17.138 | 832.079 | 30 | 5043.685 | 879.216 | |12 | 849.216 | 14.711 | 834.506 | 30 | 4209.18 | 879.216 | |13 | 849.216 | 12.277 | 836.94 | 30 | 3372.24 | 879.216 | |14 | 849.216 | 9.836 | 839.381 | 30 | 2532.86 | 879.216 | |15 | 849.216 | 7.388 | 841.829 | 30 | 1691.031 | 879.216 | |16 | 849.216 | 4.932 | 844.284 | 30 | 846.747 | 879.216 | |17 | 849.216 | 2.47 | 846.747 | 30 | 0 | 879.216 | |18 | 849.216 | 0 | 849.216 | 30 | -849.216 | 879.216 |

Total Payment amount

totalPaymentAmount <- function(loanAmount, interestRate, tenureMonths, amortizationFreeMonths = 0, invoiceFee = 0)

Total Payment amount is the sum of all payments.

Parameters

• loanAmount the total loan amount including capitalized fees (e.g. startup fee)
• interestRate the annual nominal interest
• tenureMonths the total tenure of the loan in number of months
• amortizationFreeMonths the number of initial amortization free months, default to 0
• invoiceFee a fee for each statement invoiced, default to 0

Value

returns a double containing the sum of all payments

Example

loanAmt <- 10000
tenureMonths <- 1.5 * 12
amortizationFreeMonths <- 6
interest <- 3.5 / 100
invoiceFee <- 30

totalAmt <- totalPaymentAmount(loanAmt, interest, tenureMonths, amortizationFreeMonths, invoiceFee)
print(totalAmt)

[1] 11725.645213062116

Internal Rate of Return

irr <- function(cf, precision = 1e-6)

Parameters

• cf a vector of the cash flow (see the cashFlow or paymentPlan functions)
• precision The desired accuracy to calculate the irr with (optional, default 1e-6) precision is used in the uniroot function and is assigned to the tol parameter of uniroot.

Value

returns a double containing the internal return rate

Example

Given the cache flow above

internalReturn <- irr(ppdf$cashFlow)
print(internalReturn)

[1] 0.00291665871251

Annual Percentage Rate (a.k.a. effective interest)

apr <- function(monthlyIrr)

Parameters

• monthlyIrr the MONTHLY internal rate of return (monthly irr)

Value

Returns a double with the annual percentage rate

Example

annualPercentage <- apr(internalReturn)
print(annualPercentage)

[1] 0.03556685438873

Net present value

npv <- function(i, cf, t=seq(along=cf))

Net present value (NPV) is the difference between the present value of cash inflows and the present value of cash outflows over a period of time. This function produces the same results as Excel does which differs from packages such as FinCal.

Parameters

• i interest rate
• cf cache flow e.g. the cashFlow vector of the payment plan
• t time series (optional)

Value

Returns a double with the net present value

Examples

print(npv(cf = c(-123400, 36200, 54800, 48100), i = 0.035))

[1] 5908.865636076123

Alipsa/financials documentation built on March 26, 2022, 5:59 a.m.