ALTADataSet Class

From ReliaWiki
Jump to navigation Jump to search



SynAPI.png
Main Page

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 analyze failure times and suspensions obtained under time-varying stress conditions (ALTA PRO only). Full application examples are available at Synthesis_API_Reference#Application_Examples. 

 'Declare the ALTADataSet. See ALTADataSet Constructors. 
 Dim ALTADS As New ALTADataSet
  
 'Define a single stress. See AddStressDefinition. 
 ALTADS.AddStressDefinition("Stress1", ALTASolverLSR.Exponential, 300)
          
 'Create a stress profile to describe time-varying stress conditions. See ALTAStressProfile. 
 Dim sp = New ALTAStressProfile("Profile1")
 sp.RepeatCycle = True
 sp.AddSegment(1, 250)
 sp.AddSegment(2, 300)
 sp.AddSegment(3, 400)
 
 'Add 3 exact failure times to the data set. See AddFailure. 
 ALTADS.AddFailure(10, 1, sp)
 ALTADS.AddFailure(20, 1, sp)
 ALTADS.AddFailure(30, 1, sp)
 
 'Add 3 suspensions to the data set. See AddSuspension. 
 ALTADS.AddSuspension(50, 3, sp)
 
 'Get the numbers of failure times. In this example, NumberOfFailures will be 3. See FailureCount. 
 Dim NumberOfFailures As Integer
 NumberOfFailures = ALTADataSet.FailureCount
 
 'Get the number of suspensions. In this example, NumberOfSuspension will be 3. See SuspensionCount. 
 Dim NumberOfSuspension As Integer
 NumberOfSuspension = ALTADS.SuspensionCount
 
 'Specify that the data will be fitted to a cumulative damage model combined with 
 'the Weibull life distribution. See ALTASolverModel and ALTASolverDistribution. 
 ALTADS.AnalysisSettings.ModelType = ALTASolverModel.CumDamage
 ALTADS.AnalysisSettings.Distribution = ALTASolverDistribution.Weibull
 
 'Fit the data to the model. See Calculate. 
 ALTADS.Calculate
 
 'Use the fitted model to calculate and save the reliability at time = 100. See Reliability. 
 Dim Rel As Double
 Rel = ALTADS.FittedModel.Reliability(100)
      
 'Clear the data and fitted model. See ClearDataSet. 
 ALTADS.ClearDataSet
Retrieved from "https://www.reliawiki.com/index.php?title=ALTADataSet_Class&oldid=52358"