View source for Objects and Their Attributes (con't again)

==Current Objects==

A ''Current object''  is the last object to be brought to Analytica’s attention.  If you type a command without specifying a parameter, Analytica will assume by default that you are referring to the current object, as illustrated below:

  Example>'''show Mpy'''	''(You do a "show" on variable Mpy.)'' 
  variable Mpy
  Title: miles per year
  Units: Miles/year
  Description:  Annual mileage driven
  Definition: 12K
  Nodelocation: 208,48
  Nodesize: 52,24
  Example>title		''(You ask to see the Title of the current object.)''             
  miles per year	''(This is the Title of Mpy.)''
  Example>

==Modifying Attributes==

You may add an attribute to an object, or replace an already assigned attribute, by typing the attribute to be added or replaced, the identifier of the object, a colon (":") and a new value or text string.  For example, to change the title of variable Mpy:

  Example>'''title mpy: mileage'''   ''(You replace the Title.)''
  Example>title	   ''(You ask to see the new Title for Mpy.)''
  mileage
  Example>title:miles per year	''(Original Title restored.)''
  Example>title
  miles per year
  Example>

 
You can add or replace only user-specified attributes, not computed attributes. To add or replace a definition of a variable (or another object), you type the identifier of the variable, a ":", and a new definition (you do not need to type the word "definition").  For example:

  Example>'''mpy: 20K'''

is equivalent to: 

  Example>'''Definition mpy: 20K'''

If you include the identifiers of new objects in the definition of another object, Analytica will suggest creating them.

==Deleting Objects==

The Delete command allows you to remove variables from a model.  '''You cannot undo a Delete command.'''  Analytica will automatically update outputs of the object to be deleted so that they no longer reference the object.
List Command

To see a list of all objects that belong to a particular class, you use  the List command.  For instance:

  Example>list sysfunction
  Abs        Arctan       Array        Average    Beta           
  Chance     Choose       Cinterval    Concat     Correlation    
  Cos        Cumulate     Cumulative   Density    Dydx           
  Dynamic    Elasticity   Exp          Fixarray   Fractiles      
  Getfract   If0          Ifpos        Infromrec  Linear         
  Ln         Lognormal    Makerect     Max        Maxev          
  Mean       Mid          Min          Normal     Pred           
  Product    Rank         Rankcorrel   Reform     Repeat         
  Round      Sample       Sdeviation   Sequence   Sin            
  Size       Slice        Sqr          Sqrt       Subscript      
  Sum        Table        Uncumulate   Uniform    Vvariance      
  
  
==Objects and Attributes: Summary==

Commands and other specific object identifiers are in '''bold'''.  Generic objects, such as Class class or object ''o'', are in ''italic'':

'''Show''' ''o''<br>
To list all of the user-specified attributes of an object.

'''Allshow'''<br>
To display all of the user-specified objects in a model.
class new-identifier	To create a new user-specified object (i.e., a variable, model, attribute, or function).

''o''<br>
To list a summary of an object, you type its identifier.

''attribute o''<br>	
To display a particular attribute of  an object, you type the attribute and the identifier of the object to be displayed.  If you do not type an object after the attribute, Analytica will assume the current object.

''attribute o:text''<br>
To change an attribute of a particular object.  If you do not type an object after the attribute, Analytica will assume the current object.  

''var:x''<br>
To change the definition of a variable, you type its identifier, a colon, and a new definition.

'''Delete''' ''o''<br>
To delete an object.
 
'''List''' ''class''<br>
To see all of the objects of a particular class.

'''Profile''' ''o''<br>
Command to display all the attributes of  an object o (both  user-specified and computed).  Primarily of interest to system developers.

<big>'''Concepts:'''</big>

''object'' <br>
An entity that Analytica recognizes.

''User-Created object''<br>
An object that you create (e.g., a variable,  model,  attribute, function, or version).

''System object''	<br>
An object that Analytica supplies (e.g., a command, sysfunction, keyword, sysvariable, or kind).  The user cannot create  system objects.

''attribute''	<br>
A property of an object.  For instance, variables have four attributes:  a Title, Units, Description, and Definition.

''Computed attribute''	<br>
An attribute  that Analytica computes automatically (i.e., Date, Modauthor, Inputs, outputs, Value, Probvalue, or Contains).

''User Interface attribute''	<br>
An attribute that Analytica computes using visual or other information in the user interface (i.e., Location, Nodesize, Windstate, NodeColor etc.).

''Class''	<br>
A category of object, such as command or variable.