public void PlotSignals()
{
Signal workbookSourceSignal = workBookManager.ActiveWorkBook().SumOfSources();
SignalWaveFile = null;
PlotPoints = new List <DataPoint>(512);
FrequencyViewModel = null;
// Return empty set, this clears the display when all signals are off
if (workbookSourceSignal == null)
{
NotifyPropertyChanged(nameof(PlotPoints));
NotifyPropertyChanged(nameof(FrequencyViewModel));
return;
}
CreateWavFile(workbookSourceSignal);
for (int idx = 0; idx < workbookSourceSignal.Samples.Count; idx++)
{
PlotPoints.Add(new DataPoint(idx, workbookSourceSignal.Samples[idx]));
}
//IDFT cmplxFFT = new ComplexFastFourierTransform();
IDFT cmplxFFT = new DSPGuideComplexDiscreteFourierTransform();
FrequencyDomain frequencyDomain = cmplxFFT.Transform(workbookSourceSignal.Samples, workbookSourceSignal.SamplingHZ);
FrequencyViewModel = new FrequencyHistogramViewModel(frequencyDomain);
NotifyPropertyChanged(nameof(PlotPoints));
NotifyPropertyChanged(nameof(FrequencyViewModel));
}
public void PlotData()
{
List <double> summedFilterData = manager.ActiveWorkBook().CombinedFilterImpulseResponse();
if (null == summedFilterData)
{
return;
}
Signal workbookSourceSignal = manager.ActiveWorkBook().SumOfSources();
if (workbookSourceSignal == null)
{
return;
}
SignalPlotPoints = new List <DataPoint>(workbookSourceSignal.Samples.Count);
for (int idx = 0; idx < workbookSourceSignal.Samples.Count; idx++)
{
SignalPlotPoints.Add(new DataPoint(idx, workbookSourceSignal.Samples[idx]));
}
ConvolutionPlotPoints = new List <DataPoint>(summedFilterData.Count);
for (int idx = 0; idx < summedFilterData.Count; idx++)
{
ConvolutionPlotPoints.Add(new DataPoint(idx, summedFilterData[idx]));
}
List <double> convolutionResult = convolver.Convolve(summedFilterData, workbookSourceSignal.Samples, ConvolutionType.INPUTSIDE);
ResultPlotPoints = new List <DataPoint>(convolutionResult.Count);
for (int idx = 0; idx < convolutionResult.Count; idx++)
{
ResultPlotPoints.Add(new DataPoint(idx, convolutionResult[idx]));
}
//IDFT cmplxFFT = new ComplexFastFourierTransform();
IDFT cmplxFFT = new DSPGuideComplexDiscreteFourierTransform();
FrequencyDomain frequencyDomain = cmplxFFT.Transform(convolutionResult, workbookSourceSignal.SamplingHZ);
ResultFrequencyHistogram = new FrequencyHistogramViewModel(frequencyDomain);
NotifyPropertyChanged(nameof(SignalPlotPoints));
NotifyPropertyChanged(nameof(ConvolutionPlotPoints));
NotifyPropertyChanged(nameof(ResultPlotPoints));
NotifyPropertyChanged(nameof(ResultFrequencyHistogram));
}
private void LoadFilterData()
{
List <double> summedFilterData = manager.ActiveWorkBook().CombinedFilterImpulseResponse(true);
// Return an empty set
if (summedFilterData == null || summedFilterData.Count == 0)
{
ImpulseResponsePoints = new List <DataPoint>();
StepResponsePoints = new List <DataPoint>();
FrequencyResponsePoints = new List <DataPoint>();
DecibelResponsePoints = new List <DataPoint>();
Filters = new ObservableCollection <UserControl>();
NotifyPropertyChanged(nameof(ImpulseResponsePoints));
NotifyPropertyChanged(nameof(FrequencyResponsePoints));
NotifyPropertyChanged(nameof(DecibelResponsePoints));
NotifyPropertyChanged(nameof(StepResponsePoints));
NotifyPropertyChanged(nameof(SumModeActive));
NotifyPropertyChanged(nameof(ConvolveModeActive));
NotifyPropertyChanged(nameof(Filters));
return;
}
ImpulseResponsePoints = new List <DataPoint>(summedFilterData.Count);
StepResponsePoints = new List <DataPoint>(summedFilterData.Count);
Filters = new ObservableCollection <UserControl>();
for (int idx = 0; idx < summedFilterData.Count; idx++)
{
ImpulseResponsePoints.Add(new DataPoint(idx, summedFilterData[idx]));
}
//IDFT cmplxFFT = new ComplexFastFourierTransform();
IDFT cmplxFFT = new DSPGuideComplexDiscreteFourierTransform();
int filterLength = 0;
if (manager.ActiveWorkBook().WindowedSyncFilters.Count > 0)
{
filterLength = manager.ActiveWorkBook().WindowedSyncFilters.Values.First().FilterLength;
}
else if (manager.ActiveWorkBook().CustomFilters.Count > 0)
{
filterLength = manager.ActiveWorkBook().CustomFilters.Values.First().FilterLength;
}
else
{
return; // Count not find any filters to set length with
}
FrequencyDomain frequencyDomain = cmplxFFT.Transform(summedFilterData, filterLength);
Convolution convolver = new Convolution();
List <double> stepResponse = convolver.Convolve(summedFilterData, GetStepData(summedFilterData.Count + 16), ConvolutionType.INPUTSIDE);
FrequencyResponsePoints = new List <DataPoint>(frequencyDomain.FrequencyAmplitudes.Count);
DecibelResponsePoints = new List <DataPoint>(FrequencyResponsePoints.Count);
// Load the frequency response graph data
// Only scan the first half of the coefficients (up to the Nyquist frequency)
int coefficientMax = (frequencyDomain.FourierCoefficients.Count / 2);
for (int idx = 0; idx < coefficientMax; idx++)
{
double coeffLen = Complex.Abs(frequencyDomain.FourierCoefficients[idx]);
double cuttoffFrequencyPercent = (((double)idx + 1.0) / summedFilterData.Count);
FrequencyResponsePoints.Add(new DataPoint(cuttoffFrequencyPercent, coeffLen));
DecibelResponsePoints.Add(new DataPoint(cuttoffFrequencyPercent, 20 * Math.Log10(coeffLen)));
}
int startingOffset = (summedFilterData.Count / 2);
int endingOffset = startingOffset + summedFilterData.Count;
int graphX = 0;
// Load the step response graph data
for (int idx = (startingOffset - 1); idx < endingOffset; idx++)
{
StepResponsePoints.Add(new DataPoint(graphX, stepResponse[idx]));
graphX++;
}
foreach (var filter in manager.ActiveWorkBook().WindowedSyncFilters.Values)
{
filter.PropertyChanged -= handleFilterUpdate;
WindowedSyncFilterItemView viewItem = new WindowedSyncFilterItemView();
viewItem.DataContext = filter;
Filters.Add(viewItem);
filter.PropertyChanged += handleFilterUpdate; // Remove/re-add to avoid leaks in event handlers
}
foreach (var filter in manager.ActiveWorkBook().CustomFilters.Values)
{
filter.PropertyChanged -= handleFilterUpdate;
CustomFilterViewItem viewItem = new CustomFilterViewItem();
viewItem.DataContext = filter;
Filters.Add(viewItem);
filter.PropertyChanged += handleFilterUpdate; // Remove/re-add to avoid leaks in event handlers
}
NotifyPropertyChanged(nameof(ImpulseResponsePoints));
NotifyPropertyChanged(nameof(FrequencyResponsePoints));
NotifyPropertyChanged(nameof(DecibelResponsePoints));
NotifyPropertyChanged(nameof(StepResponsePoints));
NotifyPropertyChanged(nameof(Filters));
}
public void TestComplexTransform()
{
//IDFT complexFourierTransform = new ComplexFastFourierTransform();
IDFT complexFourierTransform = new DSPGuideComplexDiscreteFourierTransform();
FrequencyDomain result;
List <double> recreatedSignal;
int sampleRate = 1000; // hz
List <double> timePoints = new List <double>(2 * sampleRate);
for (double timePointVal = 0; timePointVal < 2.0; timePointVal += (1.0 / sampleRate))
{
timePoints.Add(timePointVal);
}
List <double> signal = new List <double>(timePoints.Count);
foreach (double timePointVal in timePoints)
{
double signalValue = (2.5 * Math.Sin(2 * Math.PI * 4 * timePointVal)) + (1.5 * Math.Sin(2 * Math.PI * 6.5 * timePointVal));
signal.Add(signalValue);
}
result = complexFourierTransform.Transform(signal, sampleRate);
List <Tuple <double, double> > magPhaseList = ComplexFastFourierTransform.ToMagnitudePhaseList(result);
FrequencyDomain fromMagPhaseList = ComplexFastFourierTransform.FromMagnitudePhaseList(magPhaseList);
for (int idx = 0; idx < result.FourierCoefficients.Count; idx++)
{
double absDifference = Complex.Abs(result.FourierCoefficients[idx] - fromMagPhaseList.FourierCoefficients[idx]);
// Check that they are close, rounding error occurs, they wont be equal
Assert.IsTrue(absDifference < 1.0E-10);
}
// This file can be viewed in Excel for plotting of hz and amplitudes
StreamWriter amplitudeFile = new StreamWriter("frequencyAmplitudes.csv");
if (amplitudeFile != null)
{
amplitudeFile.WriteLine("HZ, Amplitude");
foreach (var frequencyAmplitude in result.FrequencyAmplitudes)
{
amplitudeFile.WriteLine($"{frequencyAmplitude.Key}, {frequencyAmplitude.Value}");
}
}
amplitudeFile.Close();
recreatedSignal = complexFourierTransform.Synthesize(result);
Assert.IsNotNull(result);
Assert.IsNotNull(recreatedSignal);
//double amplitude40 = result.FrequencyAmplitudes[4.0];
//double amplitude65 = result.FrequencyAmplitudes[6.5];
//Assert.IsTrue(Math.Abs(amplitude40 - 2.5) <= MaxAmplitudeDifference);
//Assert.IsTrue(Math.Abs(amplitude65 - 1.5) <= MaxAmplitudeDifference);
double maxDifference = 0.0;
for (int idx = 0; idx < recreatedSignal.Count; idx++)
{
double calculateDifference = Math.Abs(recreatedSignal[idx] - signal[idx]);
if (maxDifference < calculateDifference)
{
maxDifference = calculateDifference;
}
}
for (int idx = 0; idx < recreatedSignal.Count; idx++)
{
double calculateDifference = Math.Abs(recreatedSignal[idx] - signal[idx]);
Assert.IsTrue(calculateDifference <= MaxSignalDifference);
}
}
