/// <summary>
/// Calculates the Full Width at Half Max related values
/// </summary>
/// <param name="fullWidthHalfMaxPercent">(Optional) The threshold of where to measure the FWHM as a percent of the peak current (Default: 50%)</param>
private void CalculateFullWidthAtHalfMax(double fullWidthHalfMaxPercent = 0.5)
{
if (fullWidthHalfMaxPercent <= 0.0 || fullWidthHalfMaxPercent >= 1.0)
{
throw new ArgumentOutOfRangeException("The Full Width Half Max Percentage cannot be less than or equal to 0% or greater than or equal to 100%");
}
// Calculate what the half-max current value is (default is 50% of max amplitude)
double fullWidthHalfMaxCurrentSigned = this.PeakCurrentValue * fullWidthHalfMaxPercent;
double fullWidthHalfMaxCurrentAbsolute = fullWidthHalfMaxCurrentSigned.InvertValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Find the first (interpolated) data point that is on the rising edge of the initial spike (of the absolute value waveform)
DataPoint?fullWidthHalfMaxRisingAbsoluteDataPoint = this.AbsoluteWaveform.DataPointAtYThreshold(fullWidthHalfMaxCurrentAbsolute, true);
if (fullWidthHalfMaxRisingAbsoluteDataPoint.HasValue)
{
// Convert the rising data point to the signed value
this.FullWidthHalfMaxStartDataPoint = fullWidthHalfMaxRisingAbsoluteDataPoint.Value.InvertYValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Trim the waveform, removing everything before the max peak
Waveform absoluteWaveformAfterPeakCurrentTime = this.AbsoluteWaveform.TrimStart(this.PeakCurrentDataPoint.X);
// Find the first (interpolated) data point that is on the falling edge of the initial spike (of the absolute value waveform)
DataPoint?fullWidthHalfMaxFallingDataPointAbsolute = absoluteWaveformAfterPeakCurrentTime.DataPointAtYThreshold(fullWidthHalfMaxCurrentAbsolute, true);
if (fullWidthHalfMaxFallingDataPointAbsolute.HasValue)
{
// Convert the falling data point to the signed value
this.FullWidthHalfMaxEndDataPoint = fullWidthHalfMaxFallingDataPointAbsolute.Value.InvertYValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Find the full width half max time
this.FullWidthHalfMaxValue = this.FullWidthHalfMaxEndDataPoint.X - this.FullWidthHalfMaxStartDataPoint.X;
// Determine the min and max values for the Full Width Half Max to be passing
Tuple <double, double, double> nomMinMaxFullWidthHalfMax = CDMJS002WaveformCharacteristics.FullWidthHalfMaxNominalMinMax(this.SignedVoltage, this.IsLargeTarget, this.OscilloscopeIsHighBandwidth);
this.FullWidthHalfMaxAllowedMinimum = nomMinMaxFullWidthHalfMax.Item2;
this.FullWidthHalfMaxAllowedMaximum = nomMinMaxFullWidthHalfMax.Item3;
// Determine if the Full Width Half Max is passing
this.FullWidthHalfMaxIsPassing = DoubleRangeExtensions.BetweenInclusive(this.FullWidthHalfMaxAllowedMinimum, this.FullWidthHalfMaxAllowedMaximum, this.FullWidthHalfMaxValue);
}
else
{
// Full Width Half Max falling data point could not be found, no calculations could be made.
}
}
else
{
// Full Width Half Max rising data point could not be found, no calculations could be made.
}
}
/// <summary>
/// Calculates the Decay Time related values
/// </summary>
private void CalculateDecayTime()
{
// The percentage of the Peak Current to be the end of the decay time (1/e)
double decayTimeEndPercentOfIps = 1.0 / System.Math.E;
// Trim the waveform, removing everything before the max peak
Waveform absoluteWaveformAfterPeakCurrentTime = this.AbsoluteWaveform.TrimStart(this.PeakCurrentDataPoint.X);
// Find the start/stop times for the noise-reducing exponential fit waveform
DataPoint?expFitStartDataPoint = absoluteWaveformAfterPeakCurrentTime.DataPointAtYThreshold(0.5 * System.Math.Abs(this.PeakCurrentValue), true);
if (expFitStartDataPoint.HasValue)
{
double expFitStartTimeThreshold = expFitStartDataPoint.Value.X;
DataPoint?expFitEndDataPoint = absoluteWaveformAfterPeakCurrentTime.DataPointAtYThreshold(0.3 * System.Math.Abs(this.PeakCurrentValue), true);
// The waveform was truncated before the lower end of the decaying region,
// however there might be enough data to calculate by using the last data point instead.
if (!expFitEndDataPoint.HasValue)
{
expFitEndDataPoint = absoluteWaveformAfterPeakCurrentTime.DataPoints.Last();
}
double expFitEndTimeThreshold = expFitEndDataPoint.Value.X;
// Gate the waveform to just the area for the noise-reducing exponential fit waveform
Waveform absoluteWaveformDecayingRegion = this.AbsoluteWaveform.Gates(expFitStartTimeThreshold, expFitEndTimeThreshold);
if (absoluteWaveformDecayingRegion.DataPoints.Any())
{
// Find the exponential fit constants of the waveform from 0.5 * Ips to 0.3 * Ips to eliminate noise
Tuple <double, double> expFitAbsoluteWaveformDecayingRegionConstants = absoluteWaveformDecayingRegion.ExponentialFit();
// Create time values that go out far enough to ensure the decay time end threshold can be found
List <double> timeValues = (from dp in absoluteWaveformDecayingRegion.DataPoints select dp.X).ToList();
double samplingTime = absoluteWaveformDecayingRegion.SamplingTime();
while (timeValues.Last() < 0.000000800 && samplingTime > 0)
{
timeValues.Add(timeValues.Last() + samplingTime);
}
// Create the exponential fit equivalent waveform which has noise eliminated
Waveform expFitAbsoluteWaveformDecayingRegion = WaveformExtensions.CreateExponentialFitWaveform(
expFitAbsoluteWaveformDecayingRegionConstants.Item1,
expFitAbsoluteWaveformDecayingRegionConstants.Item2,
timeValues);
// Calculate what the decay time end threshold is (1/e % of Ips)
double decayTimeEndThreshold = System.Math.Abs(this.PeakCurrentValue) * decayTimeEndPercentOfIps;
// Find the first (interpolated) data point that is at 1/e % of Ips value (of the absolute value waveform)
DataPoint?decayTimeEndDataPointAbsolute = expFitAbsoluteWaveformDecayingRegion.DataPointAtYThreshold(decayTimeEndThreshold, true);
if (decayTimeEndDataPointAbsolute.HasValue)
{
// Convert the Decay Time end DataPoint to the signed value
this.DecayTimeEndDataPoint = decayTimeEndDataPointAbsolute.Value.InvertYValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Calculate the Decay Time
this.DecayTimeValue = this.DecayTimeEndDataPoint.X - this.PeakCurrentDataPoint.X;
// Determine if the Decay Time is passing
this.DecayTimeIsPassing = DoubleRangeExtensions.BetweenInclusive(this.DecayTimeAllowedMinimum, this.DecayTimeAllowedMaximum, this.DecayTimeValue);
}
else
{
// The derived exponential fit waveform didn't go out to a far enough time to capture the 1/e time.
}
}
else
{
// Could not find any data points in the decay time window. Likely due to a malformed waveform.
}
}
else
{
// Since the waveform was truncated before even the start of the window to calculate the decaying region, the decay time cannot be calculated.
}
}
/// <summary>
/// Calculates the Rise Time related values
/// </summary>
/// <param name="riseTimeStartPercent">Rise Time starting percentage (Default: 90%)</param>
/// <param name="riseTimeEndPercent">Rise Time ending percentage (Default: 10%)</param>
private void CalculateRiseTime(double riseTimeStartPercent, double riseTimeEndPercent)
{
if (riseTimeStartPercent < 0.0 || riseTimeStartPercent >= 1.0)
{
throw new ArgumentOutOfRangeException("The Rise Time Start % cannot be less than 0% or greater than or equal to 100%");
}
if (riseTimeEndPercent <= 0.0 || riseTimeEndPercent > 1.0)
{
throw new ArgumentOutOfRangeException("The Rise Time End % cannot be less than or equal to 0% or greater than 100%");
}
if (riseTimeStartPercent >= riseTimeEndPercent)
{
throw new ArgumentOutOfRangeException("The Rise Time Start % cannot be equal to or greater than the Rise Time End %");
}
// Generate an absolute-value version of the peak current value
double peakCurrentAbsoluteValue = this.PeakCurrentValue.InvertValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Calculate what the rise time end threshold is (a percentage of peak current)
double riseTimeEndThreshold = peakCurrentAbsoluteValue * riseTimeEndPercent;
// Find the first (interpolated) data point that is at the rise time end threshold (of the absolute value waveform)
DataPoint?riseTimeEndAbsoluteDataPoint = this.AbsoluteWaveform.DataPointAtYThreshold(riseTimeEndThreshold, true);
if (riseTimeEndAbsoluteDataPoint.HasValue)
{
// Convert the first Rise Time Data Point to the signed value
this.RiseTimeEndDataPoint = riseTimeEndAbsoluteDataPoint.Value.InvertYValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Trim the waveform, removing everything after the Rise Time End Time
Waveform absoluteWaveformUntilRiseTimeEnd = this.AbsoluteWaveform.TrimEnd(this.RiseTimeEndDataPoint.X);
// Calculate what the Rise Time Start Threshold is (a percentage of peak current)
double riseTimeStartThreshold = peakCurrentAbsoluteValue * riseTimeStartPercent;
// Find the last Data Point (interpolated) Data Point that is below the Rise Time Start Threshold (of the absolute trimmed waveform)
DataPoint?riseTimeStartAbsoluteDataPoint = absoluteWaveformUntilRiseTimeEnd.DataPointAtYThreshold(riseTimeStartThreshold, false);
if (riseTimeStartAbsoluteDataPoint.HasValue)
{
// Convert the last Rise Time Data Point to the signed value
this.RiseTimeStartDataPoint = riseTimeStartAbsoluteDataPoint.Value.InvertYValueIfNegativePolarity(this.WaveformIsPositivePolarity);
// Find the Rise Time
this.RiseTimeValue = this.RiseTimeEndDataPoint.X - this.RiseTimeStartDataPoint.X;
// Determine if the Rise Time is passing
this.RiseTimeIsPassing = DoubleRangeExtensions.BetweenInclusive(this.RiseTimeAllowedMinimum, this.RiseTimeAllowedMaximum, this.RiseTimeValue);
}
else
{
// Risetime start data point could not be found, no calculations could be made.
}
}
else
{
// Risetime end data point could not be found, no calculations could be made.
}
}