renamed and fully integrated lowpass filter

src/damaris/data/ADC_Result.py

@@ -148,7 +148,7 @@ class ADC_Result(Resultable, Drawable, DamarisFFT, Signalpath):
         return self.is_clipped
 
 
-    def digital_filter(self, cutoff, numtaps=None):
+    def lowpass(self, cutoff, numtaps=None):
         """
         Apply a zero-phase lowpass FIR filter to all channels.
 
@@ -185,12 +185,12 @@ class ADC_Result(Resultable, Drawable, DamarisFFT, Signalpath):
         Examples
         --------
         >>> # Lowpass at 1 MHz (taps auto-computed, ~40)
-        ... filtered = adc.digital_filter(cutoff=1e6)
+        ... filtered = adc.lowpass(cutoff=1e6)
         >>> # Lowpass at 500 kHz with fixed 63 taps
-        ... filtered = adc.digital_filter(cutoff=500e3, numtaps=63)
+        ... filtered = adc.lowpass(cutoff=500e3, numtaps=63)
         """
         if not self.contains_data():
-            raise RuntimeError("digital_filter: no data present")
+            raise RuntimeError("lowpass: no data present")
 
         nyquist = self.sampling_rate / 2.0
         cutoff = float(cutoff)