21 lines
711 B
C
21 lines
711 B
C
#ifndef LIGHTNING_COMMON_RANDOM_SELECT_H
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#define LIGHTNING_COMMON_RANDOM_SELECT_H
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#include "config.h"
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#include <stdbool.h>
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/* Use weighted reservoir sampling, see:
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* https://en.wikipedia.org/wiki/Reservoir_sampling#Algorithm_A-Chao
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* But (currently) the result will consist of only one sample (k=1)
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*/
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/**
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* random_select: return true if we should select this one.
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* @weight: weight for this option (use 1.0 if all the same)
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* @tot_weight: returns with sum of weights (must be initialized to zero)
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*
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* This always returns true on the first non-zero weight, and weighted
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* randomly from then on.
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*/
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bool random_select(double weight, double *tot_weight);
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#endif /* LIGHTNING_COMMON_RANDOM_SELECT_H */
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