/// <summary>
/// Calculates the distance.
/// </summary>
/// <param name="metric">The metric.</param>
/// <param name="bmu">The bmu.</param>
/// <param name="gridNeuron">The grid neuron.</param>
/// <returns>System.Double.</returns>
public double CalculateDistance(IMetric metric, IBestMatchingUnit bmu, IGridNeuron gridNeuron)
{
var distanceToBmu = metric.CalculateDistance(bmu.GridCoordinates, gridNeuron.GridCoordinates);
if (!IsToroidal)
{
return(distanceToBmu);
}
// on spherical grids, check the wrap-around distances
//
//
// X 1 2 2 1
// 1 2 3 3 2
// 2 3 4 4 3
// 1 2 3 3 2
var coordinates = gridNeuron.GridCoordinates;
var coordinatesX = new[] { coordinates[0] - Width + 2, coordinates[1] };
var coordinatesY = new[] { coordinates[0], coordinates[1] - Height + 2 };
var coordinatesXy = new[] { coordinatesX[0], coordinatesY[1] };
distanceToBmu = Math.Min(distanceToBmu, metric.CalculateDistance(bmu.GridCoordinates, coordinatesX));
distanceToBmu = Math.Min(distanceToBmu, metric.CalculateDistance(bmu.GridCoordinates, coordinatesY));
distanceToBmu = Math.Min(distanceToBmu, metric.CalculateDistance(bmu.GridCoordinates, coordinatesXy));
return(distanceToBmu);
}
/// <summary>
/// Initializes a new instance of the <see cref="BestMatchingUnit"/> class.
/// </summary>
/// <param name="bmu">The bmu.</param>
/// <param name="distance">The distance.</param>
public BestMatchingUnit(IGridNeuron bmu, double distance)
{
Distance = distance;
_bmu = bmu;
}