[Route("rooms/{id}/point")] //?firstMacId=xxx&secondMacId=yyy&thirdMacId=zzz
public IHttpActionResult GetNearestXYLocalizationPoint
([FromUri] int id, [FromUri] int firstMacId, [FromUri] int secondMacId, [FromUri] int thirdMacId, [FromUri] int fourthMacId)
{
var request = new FourRSSISignals
{
FirstMacIdRSSI = firstMacId,
SecondMacIdRSSI = secondMacId,
ThirdMacIdRSSI = thirdMacId,
FourthMacIdRRSI = fourthMacId
};
var data = _localizationServices.GetNearestXYLocalizationPoint(id, request);
return(Ok(data));
}
public Point GetNearestXYLocalizationPoint(int id, FourRSSISignals threeMacIds)
{
using (var ctx = new WifiLocalizerContext())
{
var nearestRSSIPoint = ctx.RSSIMeasurmentPoints.Where(x => x.RoomId == id)
.OrderBy(CalculteVectorsDiffExpression(threeMacIds))
.FirstOrDefault();
DatabaseHandler.PrintSuccesFetchingFromDatabase(nearestRSSIPoint);
return(new Point
{
x = nearestRSSIPoint.X,
y = nearestRSSIPoint.Y
});
}
}
private Expression <Func <RSSIMeasurmentPoint, double> > CalculteVectorsDiffExpression(FourRSSISignals fourMacIds)
{
return
(x =>
//sqare root of
(Math.Pow(
//second powers sum
Math.Pow((x.FirstMacIdRSSI - fourMacIds.FirstMacIdRSSI), 2) +
Math.Pow((x.SecondMacIdRSSI - fourMacIds.SecondMacIdRSSI), 2) +
Math.Pow((x.ThirdMacIdRSSI - fourMacIds.ThirdMacIdRSSI), 2) +
Math.Pow((x.FourthMacIdRSSI - fourMacIds.FourthMacIdRRSI), 2)
, 0.5)));
}
