Added check for valid event duration.

src/nqrduck_spectrometer/pulseparameters.py

@@ -60,6 +60,7 @@ class Function:
         mpl_widget.canvas.ax.plot(xdf, ydf)
         mpl_widget.canvas.ax.set_xlabel("Frequency in Hz")
         mpl_widget.canvas.ax.set_ylabel("Magnitude")
+        mpl_widget.canvas.ax.grid(True)
         return mpl_widget
 
     def time_domain_plot(self, pulse_length: float) -> MplWidget:
@@ -68,6 +69,7 @@ class Function:
         mpl_widget.canvas.ax.plot(td, self.evaluate(pulse_length))
         mpl_widget.canvas.ax.set_xlabel("Time in s")
         mpl_widget.canvas.ax.set_ylabel("Magnitude")
+        mpl_widget.canvas.ax.grid(True)
         return mpl_widget
     
     def get_pulse_amplitude(self, pulse_length: float) -> np.array:

src/nqrduck_spectrometer/pulsesequence.py

@@ -62,6 +62,23 @@ class PulseSequence:
                             )
 
             return obj
+        
+        @property
+        def duration(self):
+            return self._duration
+        
+        @duration.setter
+        def duration(self, duration : float):
+            # Duration needs to be a positive number
+            try:
+                duration = float(duration)
+            except ValueError:
+                raise ValueError("Duration needs to be a number")
+            if duration < 0:
+                raise ValueError("Duration needs to be a positive number")
+            
+            self._duration = duration
+            
 
     def to_json(self):
         """Returns a dict with all the data in the pulse sequence