/// <inheritdoc />
public override async Task <object> ExecuteAsync(IWorkerExecutionStatusNotificationService workerExecutionStatusNotificationService, IWorkUnit workUnit, IEnumerable <Result> dependencyResults)
{
await this.GetLogger().LogInformationAsync("PiWorker Execute", Assembly.GetExecutingAssembly().GetName().Version.ToString());
var seed = workUnit.GetHashCode();
await this.GetLogger().LogInformationAsync("PiWorker Execute", $"Random seed = {seed}");
var random = new Random(seed);
var inputData = workUnit.GetInput <PiEstimateInput>();
var numberOfSamples = inputData.NumberOfSamples;
await this.GetLogger().LogInformationAsync("PiWorker Execute", $"Input requesting NumberOfSamples={numberOfSamples}");
var numberWithinUnitCircle = 0;
for (var iteration = 0; iteration < numberOfSamples; iteration++)
{
var x = (random.NextDouble() * 2.0) - 1.0;
var y = (random.NextDouble() * 2.0) - 1.0;
var bucket = Math.Pow(x, 2.0) + Math.Pow(y, 2.0);
if (bucket <= 1.0)
{
numberWithinUnitCircle++;
}
var progress = (double)iteration / numberOfSamples;
workerExecutionStatusNotificationService?.AddWorkItemStatus(WorkStatus.Executing, progress, $"progress update {(int)progress * 100}%");
}
var result = new PiEstimateIntermediateResult
{
NumberOfSamples = numberOfSamples,
NumberWithinUnitCircle = numberWithinUnitCircle
};
await this.GetLogger().LogInformationAsync("PiWorker Execute", $"Intermediate result is NumberWithinUnitCircle={numberWithinUnitCircle}, NumberOfSamples={numberOfSamples}");
return(result);
}
public async Task <object> ReduceAsync(IWorkerExecutionStatusNotificationService workerExecutionStatusNotificationService, IWorkUnit workUnit, IEnumerable <IResult> dependencyResults)
{
try
{
await this.GetLogger().LogInformationAsync("PiWorker Reduce", Assembly.GetExecutingAssembly().GetName().Version.ToString());
var listResults = dependencyResults
.Select(r => r.GetResult <PiEstimateIntermediateResult>())
.Where(r => r != null).ToList();
var totalNumberOfSamples = listResults.Sum(r => r.NumberOfSamples);
var totalNumberWithinUnitCircle = listResults.Sum(r => r.NumberWithinUnitCircle);
var pi = 4.0 * totalNumberWithinUnitCircle / totalNumberOfSamples;
// Estimate error
const double Z = 1.96; // 95% confidence
var p = pi / 4;
var standardDeviation = Z * Math.Sqrt(p * (1 - p) / totalNumberOfSamples);
var result = new PiEstimateFinalResult
{
PI = pi,
TotalNumberOfSamples = totalNumberOfSamples,
TotalNumberWithinUnitCircle = totalNumberWithinUnitCircle,
StandardDeviation = standardDeviation
};
await this.GetLogger().LogInformationAsync("PiWorker Reduce", $"Result is Pi={pi}, Std. dev={standardDeviation:E1}, TotalNumberWithinUnitCircle={totalNumberWithinUnitCircle}, TotalNumberOfSamples={totalNumberOfSamples}");
return(result);
}
catch (Exception ex)
{
await this.GetLogger().LogErrorAsync("PiWorker Reduce", ex.Message + ex.StackTrace);
throw;
}
}
