2022-03-11 17:49:59 +01:00
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"""
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Sampling related stuff
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Such as a Sampler and Digitizer
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"""
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import numpy as np
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def quantise(signal, resolution, bias=0):
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"""
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Quantise the signal with resolution
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Parameters
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##########
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signal - arraylike
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The signal to be quantised
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resolution - float
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Resolution for quantising the signal
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bias - optional,float
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Optional bias applied before quantising
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"""
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return np.round(signal / resolution - bias) * resolution
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2022-03-24 17:48:34 +01:00
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def resample(signal, signal_fs, sample_frequency = 1):
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2022-03-11 17:49:59 +01:00
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"""
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Resample signal (sampled at signal_fs) to sample_frequency
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Parameters
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##########
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signal - arraylike
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The signal to be resampled
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signal_fs - float
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Sampling frequency of signal
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sample_frequency - float
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Wanted sampling frequency for the resampled signal
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"""
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scale = sample_frequency / signal_fs
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return _resample(signal, scale)
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def _resample(signal, scale):
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"""
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Quick resampling algorithm
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From: https://github.com/nwhitehead/swmixer/blob/master/swmixer.py
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"""
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n = round( len(signal) * scale )
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return np.interp(
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np.linspace(0, 1, n, endpoint=False), # where to interpret
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np.linspace(0, 1, len(signal), endpoint=False), # known positions
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signal, # known data points
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)
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