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38 lines
948 B
Python
38 lines
948 B
Python
import numpy as np
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import itertools
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from . import sampling
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from . import sigproc
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from . import common
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class Filter(object):
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def __init__(self, b, a=()):
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self.b = b
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self.a = a
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self.x = [0] * len(b)
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self.y = [0] * len(a)
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def __call__(self, x):
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self.x = [x] + self.x
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self.x = self.x[:len(self.b)]
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self.y = self.y[:len(self.a)]
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y = np.dot(self.x, self.b) + np.dot(self.y, self.a)
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self.y = [y] + self.y
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return y
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class FreqLoop(object):
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def __init__(self, src, freqs):
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interp = sampling.Interpolator()
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self.sampler = sampling.Sampler(src, interp)
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self.gens = []
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samplers = itertools.tee(self.sampler, len(freqs))
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for freq, generator in zip(freqs, samplers):
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gen = sigproc.extract_symbols(generator, freq)
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self.gens.append(gen)
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def __iter__(self):
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return common.izip(*self.gens)
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