/* This model demonstrates the use of the Butterworth filter facility.
The model filters a dataset, composed of a series of sinus waves with a lowpass, highpass, bandpass and bandstop filter
and uses the filtered data to create interpolation functions as function of time
that can be plotted after a kinematic analysis.

The interpolation functions used throughout the file do not serve any other purpose
than allowing one to plot the data using the charts. The filters allow you to filter any data given as an AnyFloat
and it returns to you an AnyFloat with the filtered data.
*/
Main = { 
  
  AnyFolder MyModel = { 
    /// The sample frequency
    AnyVar SampleFreq = 100;
    /// The filter orders (used for all filters)
    AnyInt FilterOrders =4;
    /// The number of samples
    AnyInt NoSamples = 1000;
     
    
    /// The time vector  
    AnyVector TestTime = iarr(0,NoSamples)*1/SampleFreq;
    /// The data vector
    AnyVector TestData =  sin(2*pi*TestTime)+sin(10*2*pi*TestTime)+sin(30*2*pi*TestTime);
    
    /// Interpolation function of the unfiltered data
    AnyFunInterpol InterPolUnFiltered = 
    {
      Type = Bspline;
      BsplineOrder = 8;
      T = .TestTime;
      Data = {.TestData};
    };
    
    AnyFloat UnfilteredInter = InterPolUnFiltered(Main.MyStudy.t);
    
    AnyFolder LowPassFilterDemo = {
      AnyVar CutOffFrequency = 10.0; // Hz 
      
      /// A lowpass butterworth filter
      AnyFunButterworthFilter LowPassFilter = 
      {
        FilterForwardBackwardOnOff = On;
        AutomaticInitialConditionOnOff = On;
        N = ..FilterOrders;
        W = {1/(..SampleFreq*0.5)*.CutOffFrequency};
        Type = LowPass;
      };
      
      // filter the data
      AnyVector Filtered = LowPassFilter(.TestData);
      
      /// Interpolation function of the lowpass filtered data
      AnyFunInterpol InterPolLowPass = 
      {
        Type = PiecewiseLinear;
        T = ..TestTime;
        Data = {.Filtered};
      };
      
      AnyFloat LowPassfilteredInter = InterPolLowPass(Main.MyStudy.t);  
    };
    
    AnyFolder HighPassFilterDemo = {
      AnyVar CutOffFrequency = 20.0; // Hz 
      /// A highpass butterworth filter
      AnyFunButterworthFilter HighPassFilter = 
      {
        FilterForwardBackwardOnOff = On;
        AutomaticInitialConditionOnOff = On;        
        N = ..FilterOrders;
        W = {1/(..SampleFreq*0.5)*.CutOffFrequency};
        Type = HighPass;
      };
      
      
      AnyVector Filtered = HighPassFilter(.TestData);
      
      /// Interpolation function of the highpass filtered data
      AnyFunInterpol InterPolHighPass = 
      {
        Type = PiecewiseLinear;
        T = ..TestTime;
        Data = {.Filtered};
      };
      
      AnyFloat HighPassfilteredInter = InterPolHighPass(Main.MyStudy.t);
      
    };
    
    
    AnyFolder BandPassFilterDemo = {
      AnyVar CutOffFrequencyLow = 10.0; // Hz 
      AnyVar CutOffFrequencyHigh = 20.0; // Hz 
      
      /// A bandpass butterworth filter
      AnyFunButterworthFilter BandPassFilter = 
      {
        FilterForwardBackwardOnOff = On;
        AutomaticInitialConditionOnOff = On;
        N = ..FilterOrders;
        W = {1/(..SampleFreq*0.5)*.CutOffFrequencyLow, 1/(..SampleFreq*0.5)*.CutOffFrequencyHigh};
        Type = BandPass;
      };    
      
      AnyVector Filtered = BandPassFilter(.TestData);
      
     
      /// Interpolation function of the bandpass filtered data
      AnyFunInterpol InterPolBandPass = 
      {
        Type = PiecewiseLinear;
        T = ..TestTime;
        Data = {.Filtered};
      };          
      
      
      AnyFloat BandPassfilteredInter = InterPolBandPass(Main.MyStudy.t);
      
    };
    
    
    AnyFolder BandStopFilterDemo = {
      AnyVar CutOffFrequencyLow = 10.0; // Hz 
      AnyVar CutOffFrequencyHigh = 20.0; // Hz 
      
      /// A bandstop butterworth filter
      AnyFunButterworthFilter BandStopFilter = 
      {
        FilterForwardBackwardOnOff = On;        
        AutomaticInitialConditionOnOff = On;        
        N = ..FilterOrders;
        W = {1/(..SampleFreq*0.5)*.CutOffFrequencyLow, 1/(..SampleFreq*0.5)*.CutOffFrequencyHigh};
        Type = BandStop;
      };    
      
      AnyVector Filtered = BandStopFilter(.TestData);
      
      /// Interpolation function of the bandstop filtered data
      AnyFunInterpol InterPolBandStop = 
      {
        Type = PiecewiseLinear;
        T = ..TestTime;
        Data = {.Filtered};
      };    
      
      AnyFloat BandStopfilteredInter = InterPolBandStop(Main.MyStudy.t);
            
    };  
  };
  
  AnyMechStudy MyStudy = 
  {
    AnyFolder &Model = .MyModel;
    tStart = 0;
    tEnd = Main.MyModel.NoSamples*1/Main.MyModel.SampleFreq;
    nStep = Main.MyModel.NoSamples+1;
    Gravity = {0, 0, 0};
    //RecruitmentSolver = MinMaxSimplex;
  };
  
};  // Main