/// <summary>
/// Called when the calibration points are changed.
/// </summary>
/// <param name="calibrationPoints">The new calibration points.</param>
protected virtual void OnCalibrationPointsChanged(CalibrationPoint[] calibrationPoints)
{
}
/// <summary>
/// Creates an instance of Windows.Devices.Sensors.Calibration
/// with the specified point count, minimum and maximum
/// reading values and calibration points.
/// </summary>
/// <param name="pointCount">The required number of calibration points.</param>
/// <param name="minimum">The minimum adjusted reading value allowed.</param>
/// <param name="maximum">The maximum adjusted reading value allowed.</param>
/// <param name="calibrationPoints">The calibrations points used to adjust the reading.</param>
public Calibration(int pointCount, float minimum, float maximum, CalibrationPoint[] calibrationPoints)
{
this.CalibrationPointCount = pointCount;
this.Minimum = minimum;
this.Maximum = maximum;
this.CalibrationPoints = calibrationPoints;
}
/// <summary>
/// Creates an instance of Windows.Devices.Sensors.NonLinearCalibration
/// with the specified point count, minimum and maximum
/// reading values and calibration points.
/// </summary>
/// <param name="minimum">The minimum adjusted reading value allowed.</param>
/// <param name="maximum">The maximum adjusted reading value allowed.</param>
/// <param name="calibrationPoints">The calibrations points used to adjust the reading.</param>
public LinearCalibration(float minimum, float maximum, CalibrationPoint[] calibrationPoints)
: base(_calibrationPointCount, minimum, maximum, calibrationPoints)
{
}
protected override void OnCalibrationPointsChanged(CalibrationPoint[] calibrationPoints)
{
this.CalculateFormulaVariables(calibrationPoints, out _m, out _b);
}
/// <summary>
/// Calculates the values a, b and c in the formula y = mx + b
/// </summary>
public virtual void CalculateFormulaVariables(CalibrationPoint[] calibrationPoints, out float m, out float b)
{
if (calibrationPoints.Length == this.CalibrationPointCount)
{
// ***
// *** These value are cast into variables here to hopefully
// *** makes this more readable
// ***
float x1 = calibrationPoints[0].X;
float x2 = calibrationPoints[1].X;
float y1 = calibrationPoints[0].Y;
float y2 = calibrationPoints[1].Y;
m = (y2 - y1) / (x2 - x1);
float b1 = m * x1;
float b2 = m * x2;
b = (b1 + b2) / 2;
}
else if (calibrationPoints.Length < this.CalibrationPointCount)
{
// ***
// *** Throw a specific exception letting the caller
// *** know there are less than the three required points.
// ***
throw new ArgumentOutOfRangeException(string.Format("There are too few points defined. {0} must be an array of three points.", nameof(calibrationPoints)));
}
else
{
// ***
// *** Throw a specific exception letting the caller
// *** know there are more than the three required points.
// ***
throw new ArgumentOutOfRangeException(string.Format("There are too many points defined. {0} must be an array of three points.", nameof(calibrationPoints)));
}
}
/// <summary>
/// Calculates the values a, b and c in the formula y = ax² + bx + c
/// </summary>
public virtual void CalculateFormulaVariables(CalibrationPoint[] calibrationPoints, out float a, out float b, out float c)
{
if (calibrationPoints.Length == this.CalibrationPointCount)
{
// ***
// *** These value are cast into variables here to hopefully
// *** makes this more readable
// ***
float x1 = calibrationPoints[0].X;
float x2 = calibrationPoints[1].X;
float x3 = calibrationPoints[2].X;
float y1 = calibrationPoints[0].Y;
float y2 = calibrationPoints[1].Y;
float y3 = calibrationPoints[2].Y;
float denom = (x1 - x2) * (x1 - x3) * (x2 - x3);
a = (x3 * (y2 - y1) + x2 * (y1 - y3) + x1 * (y3 - y2)) / denom;
b = (x3 * x3 * (y1 - y2) + x2 * x2 * (y3 - y1) + x1 * x1 * (y2 - y3)) / denom;
c = (x2 * x3 * (x2 - x3) * y1 + x3 * x1 * (x3 - x1) * y2 + x1 * x2 * (x1 - x2) * y3) / denom;
}
else if (calibrationPoints.Length < this.CalibrationPointCount)
{
// ***
// *** Throw a specific exception letting the caller
// *** know there are less than the three required points.
// ***
throw new ArgumentOutOfRangeException(string.Format("There are too few points defined. {0} must be an array of three points.", nameof(calibrationPoints)));
}
else
{
// ***
// *** Throw a specific exception letting the caller
// *** know there are more than the three required points.
// ***
throw new ArgumentOutOfRangeException(string.Format("There are too many points defined. {0} must be an array of three points.", nameof(calibrationPoints)));
}
}
/// <summary>
/// Creates an instance of Windows.Devices.Sensors.AdjustedNonLinearCalibration
/// with the specified point count, maximum
/// reading values and calibration points.
/// </summary>
/// <param name="maximum">The maximum adjusted reading value allowed.</param>
/// <param name="calibrationPoints">The calibrations points used to adjust the reading.</param>
public AdjustedNonLinearCalibration(float maximum, CalibrationPoint[] calibrationPoints)
: base(_calibrationPointCount, maximum, calibrationPoints)
{
}
