private static double getDeltaMedian(IEnumerable <IChartSeriesPointCollection> dataCollection)
{
int[] deltas = new int[dataCollection.Count() - 1];
IChartSeriesPointCollection prevPoint = null;
int index = 0;
foreach (var point in dataCollection)
{
if (null != prevPoint)
{
deltas[index++] = (int)Math.Abs(point.YValue - prevPoint.YValue);
}
prevPoint = point;
}
int numberCount = deltas.Count();
int halfIndex = deltas.Count() / 2;
var sortedNumbers = deltas.OrderBy(n => n);
double median;
if ((numberCount % 2) == 0)
{
median = (sortedNumbers.ElementAt(halfIndex) + sortedNumbers.ElementAt(halfIndex - 1)) / 2;
}
else
{
median = sortedNumbers.ElementAt(halfIndex);
}
return(median + 1);
}
private static IEnumerable <IChartSeriesPointCollection> optimizeSeriesData(IEnumerable <IChartSeriesPointCollection> dataCollection, int optimizeThresold)
{
if (optimizeThresold <= 0)
{
return(dataCollection);
}
var seriesPointList = new List <IChartSeriesPointCollection>();
IChartSeriesPointCollection prevPoint = null, pivotPoint = null, lastAddPoint = null;
long pivotDelta = 0, prevDelta = 0, prevPrevDelta;
foreach (var point in dataCollection)
{
prevPrevDelta = prevDelta;
if (null != prevPoint)
{
if (null == pivotPoint)
{
pivotPoint = point;
}
else
{
prevDelta = prevPoint.YValue - point.YValue;
pivotDelta = (pivotPoint.YValue - point.YValue);
if ((pivotDelta == 0) || (prevDelta * prevPrevDelta > 0 && Math.Abs(pivotDelta) < optimizeThresold))
{
prevPoint = point;
continue;
}
pivotPoint = point;
if (lastAddPoint != prevPoint)
{
seriesPointList.Add(prevPoint);
}
}
seriesPointList.Add(point);
lastAddPoint = point;
}
else
{
// 첫번째 포인트는 무조건 추가한다
seriesPointList.Add(point);
lastAddPoint = point;
}
prevPoint = point;
}
var lastPoint = dataCollection.ElementAt(dataCollection.Count() - 1);
if (lastAddPoint != lastPoint)
{
// 마지막 포인트도 무조건 추가
seriesPointList.Add(lastPoint);
}
return(seriesPointList);
}