R - (Object|Variable|Symbol)

Card Puncher Data Processing


R provides a number of specialized objects. They are created (instantiated), used and referenced through variable (known as symbol).

  • When you read the term object in the documentation, you can interchange it with the term variable (known as symbol)
  • The variable (known as symbol) are themselves objects

The variable (symbol) references objects.

The symbols are themselves objects and has wide ranging effects.

R have some reserved variable (system variable)


  • Numeric
> x=1
# Implicit printing of the variable
> x   
[1] 1
# Explicit printing of the variable
> print(x)

The [1] indicates that x is of the vector class

> x+x
[1] 2



The type determine the internal storage and can be seen as the primitive type of R.

See R - (Datatype|Type|Storage Mode) of an object (typeof, mode)


The class properties permits R to have an object like behavior.

R supports several class (data structure) for an object:

And you can create yours.


All objects except the NULL object can have one or more attributes.

Common R objects attributes are:

  • the element names,
  • dim(ension) attribute (e.g. matrices, arrays)
  • dimnames: the size and the name of each dimension of the object
  • class which stores the name of the class of the object
  • user-defined attributes

Attributes of an object can be listed using the attributes() function.

# data.frame object
[1] "a" "b" "c"

[1] 1 2 3 4

[1] "data.frame"

The value of a specific attribute can be obtained using the attr() function (or NULL if the attribute is not defined).

For example,

# data.frame object
attr(x, "class")
[1] "data.frame"



newname <- oldname


List current objects (objects in the workspace)


ls shows you the variables

> x <- rnorm(50)
> y <- rnorm(x)
> ls()
[1] "x" "y"



# Delete all variables for the environment
rm(list = ls())
> rm(x, y)
> ls()


newobject <- edit(object)




apropos (or find) returns a character vector of all objects matching the text searched.




Structure of an object


Fix / Edit

# Open an editor and doesn't gives the possibility to change the definition
# Open an editor and gives the possibility to change the values.



where object is an object that can be coerced to a data frame

Discover More
Card Puncher Data Processing
ORE - Install 1.3.1

grant rqrole to grant execute on rqsys.rqGroupEvalImpl for each user. Create all the synonyms listed in rquser.sql for each user. startup scriptfunctions ore.attach(USER, SID, host, password) establishes...
Card Puncher Data Processing
R - (Datatype|Type|Storage Mode) of an object (typeof, mode)

In the C code underlying R, all objects are pointers to a structure with typedef SEXPREC; the different R data types are represented in C by SEXPTYPE, which determines how the information in the various...
Card Puncher Data Processing
R - Columns

Combine objects as columns
R Studio Import Dataset
R - Data frame Object

A data frame is a logical implementation of a table in a relational database A data frame inherits all the property and function of an object. It has a list of variables of the same number of rows with...
Card Puncher Data Processing
R - Dput

Write an Object to a file or Recreate it You wil get this OS file: To make an new data frame from the created file use dget
Card Puncher Data Processing
R - Environment (Scope)

The scoping rules of a language determine how values are assigned to free variables (user variable) Free variables are not: formal arguments local variables (assigned inside the function body). ...
Card Puncher Data Processing
R - Function

Functions are stored as R objects with the class function Functions can be: used as arguments of other functions nested where: arglist is a list of argument including the three dot argument....
Card Puncher Data Processing
R - Matrix

The matrix object in R is an array of two dimensions with the same class (data type). You can create a matrix with three methods: the matrix method the columns and rows bindings methods the...
Card Puncher Data Processing
R - Names

in R. A name permits to address a value. An object may have several values and then several names. For a data.frame or a list, it will be the column header. You can set and/or get them. The...
Card Puncher Data Processing
R - Rows

Combine objects as rows

Share this page:
Follow us:
Task Runner