Show periods per DFT in GUI.

src/app.rs

@@ -47,6 +47,7 @@ pub struct App {
     pub data_frequency: Arc<AtomicF32>,
     pub single_frequency: Arc<Mutex<u32>>,
     pub dft_num: Arc<Mutex<IcdDftNum>>,
+    pub periods_per_dft: Arc<Mutex<Option<f32>>>,
 }
 
 struct TabViewer {
@@ -58,6 +59,7 @@ struct TabViewer {
     on: Arc<Mutex<bool>>,
     single_frequency: Arc<Mutex<u32>>,
     dft_num: Arc<Mutex<IcdDftNum>>,
+    periods_per_dft: Arc<Mutex<Option<f32>>>,
     show_settings: bool,
     show_settings_toggle: Option<bool>,
 }
@@ -93,6 +95,22 @@ impl TabViewer {
                             };
                         });
                     });
+                    ui.add_enabled_ui(*on, |ui| {
+                        ui.horizontal(|ui| {
+                            ui.label("Periods per DFT:");
+                            match (*on, *self.periods_per_dft.lock().unwrap()) {
+                                (true, Some(periods)) => {
+                                    ui.add(Label::new(format!("{:.2}", periods)));
+                                },
+                                (true, None) => {
+                                    ui.add(Label::new("N/A"));
+                                },
+                                (false, _) => {
+                                    ui.add(Label::new("Start to determine!"));
+                                }
+                            }
+                        });
+                    });
                 }
             });
 
@@ -337,6 +355,7 @@ impl App {
         let bode_plot = Arc::new(Mutex::new(BodePlot::new()));
         let single_frequency = Arc::new(Mutex::new(50000));
         let dft_num = Arc::new(Mutex::new(IcdDftNum::Num2048));
+        let periods_per_dft = Arc::new(Mutex::new(None));
         let on = Arc::new(Mutex::new(true));
         let tab_active = TabActive::Single;
 
@@ -349,6 +368,7 @@ impl App {
             bode_plot: bode_plot.clone(),
             single_frequency: single_frequency.clone(),
             dft_num: dft_num.clone(),
+            periods_per_dft: periods_per_dft.clone(),
             on: on.clone(),
             show_settings: false,
             show_settings_toggle: None,
@@ -370,6 +390,7 @@ impl App {
             data_frequency: Arc::new(AtomicF32::new(0.0)),
             single_frequency,
             dft_num,
+            periods_per_dft,
         };
 
         // For testing purposes, populate the Bode plot with a sample low-pass filter response