Add a function to check the fs between two Waveforms

madarrays/waveform.py

@@ -60,6 +60,14 @@ from .mad_array import MadArray
 VALID_IO_FS = {1, 8000, 16000, 32000, 48000, 11025, 22050, 44100, 88200}
 
 
+def _check_compatibility_fs(w1, w2):
+    """Raise an exception if the sampling frequency of the two Waveforms
+    are different."""
+    if w1.fs != w2.fs:
+        errmsg = 'Waveforms do not have the same fs: {} and {}.'
+        raise ValueError(errmsg.format(w1.fs, w2.fs))
+
+
 class Waveform(MadArray):
     """Subclass of MadArray to handle mono and stereo audio signals.
 
@@ -158,16 +166,14 @@ class Waveform(MadArray):
 
     def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
 
-        output = super().__array_ufunc__(ufunc, method, *inputs, **kwargs)
-
-        if isinstance(output, MadArray):
         if len(inputs) == 2:
             if (isinstance(inputs[0], Waveform) and
-                    isinstance(inputs[1], Waveform) and
-                        inputs[0].fs != inputs[1].fs):
-                    errmsg = 'Waveforms do not have the same fs: {} and {}'
-                    raise ValueError(errmsg.format(inputs[0].fs, inputs[1].fs))
+                    isinstance(inputs[1], Waveform)):
+                _check_compatibility_fs(*inputs)
 
+        output = super().__array_ufunc__(ufunc, method, *inputs, **kwargs)
+
+        if isinstance(output, MadArray):
             output = output.view(Waveform)
             output.fs = inputs[0].fs if isinstance(inputs[0], Waveform) \
                 else inputs[1].fs
@@ -773,8 +779,9 @@ class Waveform(MadArray):
         return Waveform(self)
 
     def __eq__(self, other):
-        # Test the compatability between Waveform
-        _ = self + other
+        if isinstance(other, Waveform):
+            _check_compatibility_fs(self, other)
+
         return super().__eq__(other)
 
     def is_equal(self, other):