Simu:8.1 Phase Delay finally working

lib/util.py

@@ -47,13 +47,20 @@ def time2phase(time, frequency=1):
 def phase2time(phase, frequency=1):
     return phase/(2*np.pi*frequency)
 
-def time_roll(a, samplerate, time_shift, *roll_args, int_func=lambda x: np.rint(x).astype(int), **roll_kwargs):
+def phase_modulo(phase, low=np.pi):
+    """
+    Modulo phase such that it falls within the 
+    interval $[-low, 2\pi - low)$.
+    """
+    return (phase + low) % (2*np.pi) - low
+
+def time_roll(a, samplerate, time_shift, sample_shift=0, int_func=lambda x: np.rint(x).astype(int), **roll_kwargs):
     """
     Like np.roll, but use samplerate and time_shift to approximate
     the offset to roll.
     """
-    shift = int_func(time_shift*samplerate)
-    return np.roll(a, shift, *roll_args, **roll_kwargs)
+    shift = int_func(time_shift*samplerate + sample_shift)
+    return np.roll(a, shift, **roll_kwargs)
 
 ### signal generation
 def fft_bandpass(signal, band, samplerate):