forked from jiuyuan/CPM-9G-8B
35 lines
1.0 KiB
Python
35 lines
1.0 KiB
Python
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from functools import partial
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import matplotlib.pyplot as plt
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import numpy as np
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def van_der_corput(n, base=2):
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"""Generate the n-th value in the Van der Corput sequence."""
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vdc, denom = 0, 1
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while n:
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denom *= base
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n, remainder = divmod(n, base)
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vdc += remainder / denom
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return vdc
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def van_der_corput_sampling_gen(vdc_values):
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"""Generator function for sampling indices based on weights using the Van der Corput sequence."""
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def gen(weights, vdc_value):
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cdf = np.cumsum(weights)
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sample = np.searchsorted(cdf, vdc_value)
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return sample
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sample_index = 0
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# Pre-generate Van der Corput sequence
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max_samples = 100000 # or any number that you find suitable
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while True:
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# Generate the next value in the Van der Corput sequence
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vdc_value = vdc_values[sample_index % max_samples]
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# Generate a sample index based on the Van der Corput value and the CDF
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yield partial(gen, vdc_value=vdc_value)
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sample_index += 1
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