Merge pull request #66 from swharden/numerics

FftSharp.Complex → System.Numerics.Complex

Author: swharden

README.md

@@ -15,11 +15,11 @@ var window = new FftSharp.Windows.Hanning();
 window.ApplyInPlace(signal);
 
 // Calculate the FFT as an array of complex numbers
-Complex[] fftRaw = FftSharp.Transform.FFT(signal);
+System.Numerics.Complex[] spectrum = FftSharp.FFT.Forward(signal);
 
 // or get the magnitude (units²) or power (dB) as real numbers
-double[] fftMag = FftSharp.Transform.FFTmagnitude(signal);
-double[] fftPwr = FftSharp.Transform.FFTpower(signal);
+double[] magnitude = FftSharp.FFT.Magnitude(spectrum);
+double[] power = FftSharp.FFT.Power(spectrum);
 ```
 
 Signal | Windowed Signal | FFT
@@ -32,12 +32,12 @@ Signal | Windowed Signal | FFT
 // sample audio with tones at 2, 10, and 20 kHz plus white noise
 double[] signal = FftSharp.SampleData.SampleAudio1();
 int sampleRate = 48_000;
+double samplePeriod = sampleRate / 1000.0;
 
 // plot the sample audio
-var plt = new ScottPlot.Plot(400, 200);
-plt.AddSignal(signal, sampleRate / 1000.0);
+ScottPlot.Plot plt = new();
+plt.AddSignal(signal, samplePeriod);
 plt.YLabel("Amplitude");
-plt.Margins(0);
 plt.SaveFig("time-series.png");
 ```
 
@@ -59,15 +59,15 @@ double[] signal = FftSharp.SampleData.SampleAudio1();
 int sampleRate = 48_000;
 
 // calculate the power spectral density using FFT
-double[] psd = FftSharp.Transform.FFTpower(signal);
-double[] freq = FftSharp.Transform.FFTfreq(sampleRate, psd.Length);
+System.Numerics.Complex[] spectrum = FftSharp.FFT.Forward(audio);
+double[] psd = FftSharp.FFT.Power(spectrum);
+double[] freq = FftSharp.FFT.FrequencyScale(psd.Length, sampleRate);
 
 // plot the sample audio
-var plt = new ScottPlot.Plot(400, 200);
+ScottPlot.Plot plt = new ScottPlot.Plot();
 plt.AddScatterLines(freq, psd);
 plt.YLabel("Power (dB)");
 plt.XLabel("Frequency (Hz)");
-plt.Margins(0);
 plt.SaveFig("periodogram.png");
 ```
 
@@ -82,12 +82,12 @@ plt.SaveFig("periodogram.png");
 If you are writing a performance application or just enjoy working with real and imaginary components of complex numbers, you can build your own complex array perform FFT operations on it in place:
 
 ```cs
-Complex[] buffer =
+System.Numerics.Complex[] buffer =
 {
-    new Complex(42, 0),
-    new Complex(96, 0),
-    new Complex(13, 0),
-    new Complex(99, 0),
+    new(real: 42, imaginary: 12),
+    new(real: 96, imaginary: 34),
+    new(real: 13, imaginary: 56),
+    new(real: 99, imaginary: 78),
 };
 
 FftSharp.Transform.FFT(buffer);

src/FftSharp.Demo/FftSharp.Demo.csproj

@@ -20,9 +20,9 @@
         <PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
         <PackageReference Include="NAudio" Version="1.10.0" />
         <PackageReference Include="runtime.osx.10.10-x64.CoreCompat.System.Drawing" Version="5.8.64" />
-        <PackageReference Include="ScottPlot" Version="4.1.27" />
-        <PackageReference Include="ScottPlot.WinForms" Version="4.1.27" />
+        <PackageReference Include="ScottPlot" Version="4.1.63" />
+        <PackageReference Include="ScottPlot.WinForms" Version="4.1.63" />
         <PackageReference Include="System.Data.DataSetExtensions" Version="4.5.0" />
-        <PackageReference Include="System.Drawing.Common" Version="4.7.0" />
+        <PackageReference Include="System.Drawing.Common" Version="*" />
     </ItemGroup>
 </Project>

src/FftSharp.Demo/FormAudio.cs

@@ -1,4 +1,5 @@
-using System;
+using ScottPlot.Drawing.Colormaps;
+using System;
 using System.Collections.Generic;
 using System.ComponentModel;
 using System.Data;
@@ -117,7 +118,8 @@ private void UpdateWindowed(double[] audio)
 
         private void UpdateFFT(double[] audio)
         {
-            double[] ys = cbLog.Checked ? Transform.FFTpower(audio) : Transform.FFTmagnitude(audio);
+            System.Numerics.Complex[] spectrum = FftSharp.FFT.Forward(audio);
+            double[] ys = cbLog.Checked ? FftSharp.FFT.Power(spectrum) : FftSharp.FFT.Magnitude(spectrum);
             string yLabel = cbLog.Checked ? "Power (dB)" : "Magnitude (RMS²)";
 
             plotFFT.Plot.Clear();