peek-methods: Have a look at the first element from an object without...

In datastructures: Implementation of Core Data Structures

Description

Peeks into an object, i.e. takes the first element and returns it without removing it from the object. The data structure that has a peek method usually uses some sort of priority of its elements.

Usage

peek(obj)

## S4 method for signature 'deque'
peek(obj)

## S4 method for signature 'heap'
peek(obj)

## S4 method for signature 'map'
peek(obj)

Arguments

obj	the object to peek

Value

returns the first element from obj as list

Examples

 # peeks into a queue
 q <- queue()
 q <- insert(q, list(environment(), data.frame(a=1)))
 peek(q)

 # peeks into a fibonacci heap
 b_heap <- binomial_heap()
 b_heap <- insert(b_heap, letters[seq(3)], list(1, diag(3), rnorm(2)))
 peek(b_heap)

 # peeks into a \code{hashmap}
 h_map <- hashmap()
 h_map[letters] <- rnorm(length(letters))
 peek(h_map)

 # peeks into a \code{bimap}
 b_map <- bimap("integer", "integer")
 b_map[seq(10)] <- seq(10, 1)
 peek(b_map)

datastructures documentation built on Aug. 10, 2020, 5:08 p.m.