Difference between revisions of "User Reference:ConditionalIntegrator"

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(IntegrationCondition)
 
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A [[User Reference:Expression Syntax|boolean expression]] that determines whether the signal is integrated.
 
A [[User Reference:Expression Syntax|boolean expression]] that determines whether the signal is integrated.
 
When the expression first evaluates to ''true'', the filter's output is set to zero.
 
When the expression first evaluates to ''true'', the filter's output is set to zero.
Then, while the expression evaluates to ''true'', filter input is integrated, and the integral is returned as the filter output.
+
Then, while the expression evaluates to ''true'', filter input is integrated, and the integral's current value is returned as the filter output.
When the expression first evaluates to ''false'', filter output is constant, until the expression again evaluates to ''true''.
+
When the expression first evaluates to ''false'', filter output will be kept at the last integration value, and will stay there until the expression again evaluates to ''true''.
  
 
==States==
 
==States==

Latest revision as of 10:04, 10 March 2008

Function

The ConditionalIntegrator filter accumulates (integrates) its input signal over time, depending on the value of a given boolean expression.

Typically, the ConditionalIntegrator is used in off-line analysis of data collected in a cursor movement paradigm. During on-line operation, the feedback cursor's position represents the integral of the control signal. For off-line parameter simulation experiments, the ConditionalIntegrator performs this integration, resulting in an output equivalent to cursor position on the feedback screen.

Parameters

IntegrationCondition

A boolean expression that determines whether the signal is integrated. When the expression first evaluates to true, the filter's output is set to zero. Then, while the expression evaluates to true, filter input is integrated, and the integral's current value is returned as the filter output. When the expression first evaluates to false, filter output will be kept at the last integration value, and will stay there until the expression again evaluates to true.

States

Any existing state may be part of the IntegrationCondition expression.

Example

A typical feedback task sets the Feedback state to 1 during cursor movement. Accordingly, one would use

IntegrationCondition= Feedback

in an off-line simulation.

See also

User Reference:Expression Syntax, User Reference:StateTransform