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88 lines
2.1 KiB
Python
88 lines
2.1 KiB
Python
''' Common package functionality.
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'''
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import itertools
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import numpy as np
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import logging
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log = logging.getLogger(__name__)
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scaling = 32000.0 # out of 2**15
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def load(fileobj):
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''' Load signal from file object. '''
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return loads(fileobj.read())
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def loads(data):
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''' Load signal from memory buffer. '''
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x = np.frombuffer(data, dtype='int16')
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x = x / scaling
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return x
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def dumps(sym):
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''' Dump signal to memory buffer. '''
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sym = sym.real * scaling
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return sym.astype('int16').tostring()
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def iterate(data, size, func=None, truncate=True, index=False):
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''' Iterate over a signal, taking each time *size* elements. '''
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offset = 0
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data = iter(data)
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done = False
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while not done:
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buf = list(itertools.islice(data, size))
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if len(buf) < size:
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if truncate or not buf:
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return
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done = True
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result = func(buf) if func else np.array(buf)
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yield (offset, result) if index else result
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offset += size
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def split(iterable, n):
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''' Split an iterable of n-tuples into n iterables of scalars.
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The k-th iterable will be equivalent to (i[k] for i in iter).
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'''
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def _gen(it, index):
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for item in it:
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yield item[index]
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iterables = itertools.tee(iterable, n)
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return [_gen(it, index) for index, it in enumerate(iterables)]
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def icapture(iterable, result):
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''' Appends each yielded item to result. '''
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for i in iter(iterable):
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result.append(i)
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yield i
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def take(iterable, n):
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''' Take n elements from iterable, and return them as a numpy array. '''
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return np.array(list(itertools.islice(iterable, n)))
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def izip(iterables):
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''' "Python 3" zip re-implementation for Python 2. '''
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iterables = [iter(iterable) for iterable in iterables]
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while True:
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yield tuple([next(iterable) for iterable in iterables])
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class Dummy(object):
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''' Dummy placeholder object for testing and mocking. '''
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def __getattr__(self, name):
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return self
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def __call__(self, *args, **kwargs):
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return self
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