---
title: "CapitalR"
author: "John T. Buynak"
date: "`r Sys.Date()`"
output: rmarkdown::html_vignette
vignette: >
  %\VignetteIndexEntry{CapitalR}
  %\VignetteEngine{knitr::rmarkdown}
  %\VignetteEncoding{UTF-8}
---


## Functions

##### Annuity Loan Calculation
Calculates the payment, present value, future value, rate, or the number of periods

$annuity(type = "pmt", pv = -2000, fv = 0, n  = 4 * 12, r = 0.06/12, end = TRUE)$

* `type` Select the loan parameter to return:
    + `"pmt"` Periodic Payment
    + `"pv"` Present Value
    + `"fv"` Future Value
    + `"nper"` Number of Periods
    + `"rate"` Rate
* `r` Periodic Rate
* `n` Number of Periods
* `end` Logical. If `FALSE` payments are made at the beginning of the period

##### Interest Payment
Calculates the interest portion of the periodic payment at period "x"

$ipmt(pv = 20000, fv = 0, n = 5 * 12, r = 0.05/12, x = 12, end = TRUE)$

- `pv` Present Value
- `fv` Future Value
- `r` Periodic Rate
- `n` Number of Periods
- `x` Period 
- `end` Logical. If `FALSE` payments are made at the beginning of the period


##### Principal Payment
Calculates the principal portion of the periodic payment at period "x"

$ppmt(pv = 20000, fv = 0, n = 5 * 12, r = 0.05/12, x = 12, end = TRUE)$

- `pv` Present Value
- `fv` Future Value
- `r` Periodic Rate
- `n` Number of Periods
- `x` Period 
- `end` Logical. If `FALSE` payments are made at the beginning of the period


##### Amortization Schedule
Returns the loan amortization schedule

$schedule(r = 0.06/12, n = 10 * 12, pv = -5000, fv = 0, end = TRUE)$

- `pv` Present Value
- `fv` Future Value
- `r` Periodic Rate
- `n` Number of Periods
- `end` Logical. If `FALSE` payments are made at the beginning of the period

##### Amortization Schedule with Irregular Payments
Returns the loan amortization schedule with irregular payments

$irregular(payments = c(0, 200, -100, 500), dates = c("2019-01-01", "2019-02-08", "2019-03-20", "2019-05-05"), apr = 0.05, pv = 2000, info = TRUE)$

- `payments` Vector of payments, inital payment must be 0
- `dates` Vector of Dates in which payments take place
- `apr` Annual Percent Rate
- `pv` Present Value
- `info` Logical. If set to 'TRUE', information about the dataframe arrangement will be printed

##### Present Value
 
 $pv(fv = 20000, n = 5 * 12, r = 0.08 / 12)$
 
 - `fv` Future Value
 - `n` Number of Periods
 - `r` Discount Rate
 
##### Future Value

 $fv(pv = 20000, n = 5 * 12, r = 0.08 / 12)$
 
 - `pv` Present Value
 - `n` Number of Periods
 - `r` Discount Rate

##### Geometric Mean Return
Computes the geometric mean return of a vector of periodic returns in decimal form

$geometric(c(0.20, 0.05, -0.50, 0.75, 0.25))$

##### Return Calculation
Calculates the periodic return, supply a vector of numerical asset prices

$r.calc(c(80, 65, 70, 75, 90, 105))$