## EditExpr

### Description

Opens the Expression Editor for the expressions on the given parameters.
An expression is a string of characters that may include object and parameter names, mathematical operators, and tokens representing functions or constants. For example, to constrain object A's Y rotation to object B's X translation, you would set an expression on A.kine.local.roty consisting of the string B.kine.local.posx.
An expression is a mathematical formula that you can use to control any parameter that can be animated, such as translation, rotation, scaling, material, or texture. You can create almost any connection you like between parameters, from simple "A = B" relationships to very complex ones using predefined variables, standard math functions, random number generators, and more.
For more information on expressions, see the Animation guide.

### Scripting Syntax

    EditExpr( [InputObj] );

### Parameters

Parameter | Type | Description
--- | --- | ---
InputObj | String | List of parameters (for example "cone*/kine.local.pos"). Default Value: Currently selected and marked parameters

### Examples

#### VBScript Example

    '

    ' This example sets an expression on a parameter using the SetExpr

    ' command and then uses the EditExpr command to open the Expression

    ' Editor to inspect the new expression.

    '

    NewScene , false

    ' Create the object on which to set the expression

    set oDonut = CreatePrim( "Torus", "NurbsSurface" )

    ' Make sure the last frame will be set to 100

    SetValue "PlayControl.Out", 100

    ' Set a key frame at frame 1, with XPos = -30

    SaveKey oDonut & ".kine.local.posx", 1, -30

    ' Set another key frame at frame 100, with XPos = 30

    SaveKey oDonut & ".kine.local.posx", 100, 30

    ' Temporarily disable cycle checking (this

    ' expression creates a cycle on purpose)

    bCyclePref = GetValue( "preferences.data_management.disable_cycle_checking" )

    SetValue "preferences.data_management.disable_cycle_checking", True

    ' Animate the YPos parameter with an expression

    SetExpr oDonut & ".kine.local.posy", _

    		"5*sin(" & oDonut & ".kine.local.posx * 15)"

    ' Restore cycle checking to its previous value

    SetValue "preferences.data_management.disable_cycle_checking", bCyclePref

    ' Now display the Expression Editor to see the results

    EditExpr oDonut & ".kine.local.posy"

### See Also

Expression AddExpr SetExpr RemoveAnimation