stack-class

isEmpty,stack-method

mpush,stack-method

pop,stack-method

push,stack-method

show,stack-method

top,stack-method

A stack implementation using a <code>filehash</code> database

classes

Implements a simple key-value style database where character string keys
are associated with data values that are stored on the disk. A simple interface is provided for inserting,
retrieving, and deleting data from the database. Utilities are provided that allow 'filehash' databases to be
treated much like environments and lists are already used in R. These utilities are provided to encourage
interactive and exploratory analysis on large datasets. Three different file formats for representing the
database are currently available and new formats can easily be incorporated by third parties for use in the
'filehash' framework.

Roger D Peng

filehash

Simple Key-Value Database

stack-class function

Objects can be created by calls of the form <code>new("stack", ...)</code> or
by calling <code>createS</code>. Existing queues can be initialized with
<code>initS</code>.

Objects from the Class

<dl>
 <dt><code>stack</code>:</dt>
<dd>Object of class <code>"filehashDB1"</code></dd> <dt><code>name</code>:</dt>
<dd>Object of class <code>"character"</code>: the name of
 the stack (default is the file name in which the stack data are
 stored)</dd> 
</dl>

Slots

<dl>
 <dt>isEmpty</dt>
<dd><code>signature(db = "stack")</code>: returns
 <code>TRUE</code>/<code>FALSE</code> depending on whether there are elements
 in the stack.</dd> <dt>pop</dt>
<dd><code>signature(db = "stack")</code>: returns the value of the
 top of the stack and subsequently removes that
 element from the stack; an error is signaled if the stack is empty</dd> <dt>push</dt>
<dd><code>signature(db = "stack")</code>: adds an element to the
 top of the stack</dd> <dt>show</dt>
<dd><code>signature(object = "stack")</code>: prints the name of
 the stack</dd> <dt>top</dt>
<dd><code>signature(db = "stack")</code>: returns the value of the
 top of the stack; an error is signaled if the stack
 is empty</dd> <dt>mpush</dt>
<dd><code>signature(db = "stack")</code>: works like <code>push</code>
 except it can push multiple objects in a list on to the stack</dd> 
</dl>

Methods

Roger D. Peng <a href="/link/rpeng%40jhsph.edu?package=filehash&version=2.4-3" data-mini-rdoc="filehash::rpeng@jhsph.edu">rpeng@jhsph.edu</a>

Author

Class "stack" — stack-class

<dl>
 <dt><code>stack</code>:</dt>
<dd>Object of class <code>"filehashDB1"</code></dd>

 <dt><code>name</code>:</dt>
<dd>Object of class <code>"character"</code>: the name of
 the stack (default is the file name in which the stack data are
 stored)</dd>

 
</dl>

<dl>
 <dt>isEmpty</dt>
<dd><code>signature(db = "stack")</code>: returns
 <code>TRUE</code>/<code>FALSE</code> depending on whether there are elements
 in the stack.</dd>

 <dt>pop</dt>
<dd><code>signature(db = "stack")</code>: returns the value of the
 top of the stack and subsequently removes that
 element from the stack; an error is signaled if the stack is empty</dd>

 <dt>push</dt>
<dd><code>signature(db = "stack")</code>: adds an element to the
 top of the stack</dd>

 <dt>show</dt>
<dd><code>signature(object = "stack")</code>: prints the name of
 the stack</dd>

 <dt>top</dt>
<dd><code>signature(db = "stack")</code>: returns the value of the
 top of the stack; an error is signaled if the stack
 is empty</dd>

 <dt>mpush</dt>
<dd><code>signature(db = "stack")</code>: works like <code>push</code>
 except it can push multiple objects in a list on to the stack</dd>

 
</dl>

Roger D. Peng <a href='mailto:rpeng@jhsph.edu'>rpeng@jhsph.edu</a>

stack-class: Class "stack"

Description

Arguments

Objects from the Class

Slots

Methods

Author

Examples