ALTADataSet Class: Difference between revisions

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Line 84: Line 84:
   ADS.AddFailure(92, 1, 426)
   ADS.AddFailure(92, 1, 426)
    
    
  {{APIComment|'Fit failure times to a model}}
  {{APIComment|'Fit failure times to the specified model}}
   ADS.Calculate()
   ADS.Calculate()
    
    

Revision as of 15:22, 27 March 2014


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.

Constructors

  • ALTADataSet Creates a new ALTADataSet object with an empty data set name.
  • ALTADataSet( String ) Creates a new ALTADataSet object with the user-specified data set name.

Methods

Use these methods to enter data points into a data sheet and analyze them. The settings for the analysis are specified with this class's properties.

Add Stresses and Stress Profiles

Add/Remove Data

Analyze Data

  • Calculate Fits the model (i.e., distribution and life-stress relationship) to the current data set using the settings specified in the AnalysisSettings property.

Properties

Use these properties to specify analysis settings and view analysis results, as well as view or edit properties of the data set.

Analysis Settings

Analysis Results

  • FittedModel (as cModel) Gets the fitted model from the accelerated life testing analysis.
  • AnalysisResults (as ALTAAnalysisResults) Gets the likelihood function value that was estimated from the analysis.

Data Set Properties

  • DatasetName (as string) Provides the ability to retrieve or set the name of the data set.
  • FailureCount (as integer) Gets the total number of failures in the data set.
  • SuspensionCount (as integer) Gets the total number of suspensions in the data set.
  • NumStresses (as integer) Gets the total number of stresses in the data set.

Events

The ALTAEvents class contains 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.

Usage Example

This example demonstrates how to fit three failure times to a model and then use the model to calculate the reliability at a specified time. Full application examples are available at Synthesis_API_Reference#Application_Examples.

 'Initialize a new ALTADataSet object 
 Dim ADS As New ALTADataSet("DataSet1")
 
 'Set analysis settings 
 ADS.AnalysisSettings.ModelType = ALTASolverModel.Arrhenius
 ADS.AnalysisSettings.Distribution = ALTASolverDistribution.Weibull
 ADS.AnalysisSettings.Analysis = ALTASolverMethod.MLE
 ADS.AnalysisSettings.UngroupGroupedData = False
 ADS.AnalysisSettings.SortBeforeCalculations = True
 
 'Set general settings 
 ADS.GeneralSettings.AllowLargeBetaValues = False
 ADS.GeneralSettings.ImplementStressAtTheEndOfTheStep = False
 
 'Add a stress definition 
 ADS.AddStressDefinition("Temperature (K)", , 400)
 
 'Add failure times 
 ADS.AddFailure(248, 1, 406)
 ADS.AddFailure(164, 1, 416)
 ADS.AddFailure(92, 1, 426)
 
 'Fit failure times to the specified model 
 ADS.Calculate()
 
 'Get the reliability at 300 hours 
 Dim Rel As Double
 Rel = ADS.FittedModel.Reliability(300)