# getEventProb: Calculate the probability of a specified set of dice-rolling... In dice: Calculate probabilities of various dice-rolling events

## Description

For a specified dice-rolling process, `getEventProb` calculates the probability of an event (i.e., a non-empty set of outcomes) that is specified by passing a `list` object in to `eventList`.

## Usage

 `1` ```getEventProb(nrolls, ndicePerRoll, nsidesPerDie, eventList, orderMatters = FALSE) ```

## Arguments

 `nrolls` A single positive integer representing the number of dice rolls to make `ndicePerRoll` A single positive integer representing the number of dice to use in each dice roll `nsidesPerDie` A single positive integer representing the number of sides on each die (`getEventProb`'s dice-rolling process involves only one type of die per call) `eventList` A `list` object, each element of which is a vector that constrains a single dice roll in the dice-rolling process (see Details below) `orderMatters` A logical flag indicating whether the order of the elements of `eventList` should constrain the event space; if TRUE, `eventList` must specify constraints for every dice roll–i.e., it must contain exactly `nrolls` elements (some of which may be "empty" constraints listing all possible outcomes of a dice roll, i.e., a vector from `ndicePerRoll` to `(ndicePerRoll * nsidesPerDie)`)

## Details

The crux of this function is `eventList`, which sets the conditions that acceptable dice-rolls must meet. E.g., to get the probability of rolling at least one 6 when rolling four six-sided dice, `eventList` would be `list(6)` and `orderMatters` would be FALSE; to get the probability of rolling a 6, followed by a 5, followed by either a 1, 2, or 3 when rolling three six-sided dice, `eventList` would be `list(6,5,1:3)` and `orderMatters` would be TRUE.

## Value

A single number representing the probability of an event that meets the constraints of the specified dice-rolling process

Dylan Arena

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22``` ```## Probability of rolling at least one 6 when rolling four six-sided dice getEventProb(nrolls = 4, ndicePerRoll = 1, nsidesPerDie = 6, eventList = list(6)) ## Probability of rolling a 6, followed by a 5, followed by either a 1, 2, ## or 3 when rolling three six-sided dice getEventProb(nrolls = 3, ndicePerRoll = 1, nsidesPerDie = 6, eventList = list(6, 5, 1:3), orderMatters = TRUE) ## Probability of rolling no 10's when rolling two ten-sided dice getEventProb(nrolls = 2, ndicePerRoll = 1, nsidesPerDie = 10, eventList = list(1:9,1:9)) ```

dice documentation built on May 29, 2017, 4:12 p.m.