ALTADataSet Class

Provides Provides the functionality of an ALTA standard folio, including entering data in a data set, specifying analysis settings and fitting a distribution and life-stress relationship to the data set. To create plots, use the WAPlots class.

General options for ALTADataSet can be found in ALTAGeneralOptions.

Constructors

This section contains information on how to create a new ALTA folio.

• New ALTADataSet Provides an application to create a new ALTADataSet class that represents the data to fit ALTA raw data. Use this to create a new ALTA data set.

Methods

This section contains the methods that a user might use to manipulate their ALTA data set. A user may use these methods to add columns, add stress profiles, add failures, add failure intervals, add suspension internals, calculate the data set, or clear the data set. This section should be configured after the data set has been created.

• AddFailure Adds a failure time and associated stress level to the data set.
• AddFailureInterval Adds a failure interval and associated stress level to the data set.
• AddStressDefinition Adds a stress to the data set, using the specified name of the stress, the stress transformation (if any) and the use stress level.
• AddStressProfile Makes an existing time-varying stress profile available for use in the analysis.
• AddSuspension Adds a suspension and associated stress level to the data set.
• AddSuspensionInterval Adds a suspension interval and associated stress level to the data set.
• Calculate Fits the model (i.e., distribution and life-stress relationship) to the current data set using the settings specified in the AnalysisSettings property.
• ClearDataSet Clears all data and stresses in the data set, and removes the fitted model, if any.

Properties

This section contains properties that a user may use to analyse the data set. The user may choose to have a data set name, have a count of failures, or set a life stress relationship.

• AnalysisResults Gets the likelihood function value that was estimated from the analysis.
• AnalysisSettings Sets some of the control panel analysis settings for use with the ALTADataSet.Calculate method.
• DatasetName Provides the ability to retrieve or set the name of the data set.
• FailureCount Returns the failure count within an ALTA data set.
• FittedModel Gets the fitted model from the accelerated life testing analysis.
• GeneralSettings Sets some of the Application Setup calculation options that can apply to the ALTADataSet.Calculate method.
• NumStresses Gets the total number of stresses in the data set.
• PlotUseStress Sets or gets the use stress value of a particular stress for use in plots (not calculations), using the specified stress index.
• StressRelation Sets or gets the stress transformation of a particular stress, using the specified stress index.
• SuspensionCount Returns the number of suspensions entered in the data set.

Events

This section allows the user to display events.

ALTAEvents contains only methods.

• ALTAEvents all the event handlers that can be called by ALTADataSet. To use events, you must inherit the class, override its methods and assign its instance to the Events property of an ALTADataSet. ALTAEvents inheritance is not available in VB6/VBA.

Formatted Usage Example

This examples only uses constructors, methods, and properties found in WeibullDataSet.

Declare the ALTADataSet. See New ALTADataSet for additional details.

       Dim ALTADS as New ALTADataSet

Declare an ALTAStressProfile. See ALTAStressProfile for additional details.

       Dim sp = New ALTAStressProfile("Profile1")
       sp.RepeatCycle = True
       sp.AddSegment(1, 250)
       sp.AddSegment(2, 300)
       sp.AddSegment(3, 400)

Add failure values to the raw data. See AddFailure for additional details.

       ALTADS.AddFailure(1, 1, sp)
       ALTADS.AddFailure(2, 1, sp)
       ALTADS.AddFailure(3, 1, sp)

Add suspension values to the raw data.See AddSuspension for additional details.

       ALTADS.AddSuspension(1, 1, sp)
       ALTADS.AddSuspension(2, 1, sp)
       ALTADS.AddSuspension(3, 1, sp)

Get the number of failures. In this example, NumberOfFailures will be 3. See FailureCount for additional details.

       Dim NumberOfFailures as Integer
       NumberOfFailures = ALTADataSet.FailureCount

Get the number of suspensions. In this example, NumberOfSuspension will be 3. SeeSuspensionCount for additional details.

       Dim NumberOfSuspension as Integer
       NumberOfSuspension = ALTADS.SuspensionCount

Calculate the ALTADataSet. See Calculate for additional details.

       ALTADS.Calculate

Use ClearDataSet to clear data and fitted model. See ClearDataSet for additional details. }}

       ALTADS.ClearDataSet

Get the number of failures. In this example, NumberOfFailures will be 0. See FailureCount for additional details. }}

       Dim NumberOfFailures as Integer
       NumberOfFailures = ALTADS.FailureCount