public void TestSmallerOutOfBounds()
{
var b = new BucketSize(0.00022M);
Assert.Equal(0.0002M, b.SnappedSize);
Assert.Equal(0.0001M, b.Smaller(1)?.SnappedSize);
Assert.Null(b.Smaller(2));
}
public void TestSmaller()
{
var b = new BucketSize(80);
Assert.Equal(100M, b.SnappedSize);
Assert.Equal(20M, b.Smaller(2).SnappedSize);
}
internal static decimal[] EstimateBucketResolutions(
long numSamples,
double minSample,
double maxSample,
long valuesPerBucketTarget,
bool isIntegerColumn)
{
if (numSamples <= 0)
{
throw new System.ArgumentException(
$"Argument numSamples should always be greater than zero, got {numSamples}.");
}
var range = maxSample - minSample;
if (range <= 0)
{
return(new decimal[] { 1M });
}
var valueDensity = numSamples / (maxSample - minSample);
var targetBucketSize = valuesPerBucketTarget / valueDensity;
var bucketSizeEstimate = new BucketSize(isIntegerColumn
? System.Math.Max(targetBucketSize, 5)
: targetBucketSize);
return(new decimal[]
{
bucketSizeEstimate.Smaller(steps: 2).SnappedSize,
bucketSizeEstimate.SnappedSize,
bucketSizeEstimate.Larger(steps: 2).SnappedSize,
});
}
