feat: added Oscilloscope functionality

lib/communication/analytics_class.dart

@@ -30,6 +30,7 @@ class AnalyticsClass {
 
     complex = fft(yReal2.map((x) => Complex(x)).toList());
     yHat = fftToRfft(complex);
+    yHatSquare = List<double>.filled(yHat.length, 0);
     for (int i = 0; i < yHat.length; i++) {
       yHatSquare[i] = pow(yHat[i], 2).toDouble();
       if (yHatSquare[i] > maximum) {
@@ -125,7 +126,7 @@ class AnalyticsClass {
     }
 
     double amplitude = (sumGreaterThanOffset / n1) - (sumLesserThanOffset / n2);
-    List<bool> bools = [];
+    List<bool> bools = List.filled(yTmp.length - 1, false);
     double tmp;
     for (int i = 0; i < yTmp.length - 1; i++) {
       tmp = yTmp[i + 1] - yTmp[i];

lib/others/oscilloscope_axes_scale.dart

@@ -0,0 +1,61 @@
+class OscillscopeAxesScale {
+  late double _yAxisScale;
+  late double _yAxisScaleMin;
+  late double _yAxisScaleMax;
+  late double _xAxisScale;
+
+  OscillscopeAxesScale() {
+    _yAxisScale = 16;
+    _yAxisScaleMin = -16;
+    _yAxisScaleMax = 16;
+    _xAxisScale = 875;
+  }
+
+  double get yAxisScale => _yAxisScale;
+  double get yAxisScaleMin => _yAxisScaleMin;
+  double get yAxisScaleMax => _yAxisScaleMax;
+  double get xAxisScale => _xAxisScale;
+
+  void setYAxisScale(double value) {
+    _yAxisScale = value;
+    _yAxisScaleMax = value;
+    _yAxisScaleMin = -value;
+  }
+
+  void setYAxisScaleMin(double value) {
+    _yAxisScaleMin = value;
+  }
+
+  void setYAxisScaleMax(double value) {
+    _yAxisScaleMax = value;
+  }
+
+  void setXAxisScale(double value) {
+    _xAxisScale = value;
+  }
+
+  double getTimebaseInterval() {
+    switch (_xAxisScale) {
+      case 875.00:
+        return 100;
+      case 1000.00:
+        return 0.2;
+      case 2000.00:
+        return 0.3;
+      case 4000.00:
+        return 0.7;
+      case 8000.00:
+        return 1;
+      case 25600.00:
+        return 4;
+      case 38400.00:
+        return 10;
+      case 51200.00:
+        return 10;
+      case 102400.00:
+        return 20;
+      default:
+        return _xAxisScale / 5000;
+    }
+  }
+}