46 lines
865 B
C
46 lines
865 B
C
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/*
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* Copyright (c) 2009 Juan Gonzalez de Benito.
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*
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* Licensed under the BSD License, see LICENSE file for details.
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*
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*/
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#ifndef CPP_INCLUDE_UTIL_ZIPF_GENERATOR_H_
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#define CPP_INCLUDE_UTIL_ZIPF_GENERATOR_H_
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namespace xtreemfs {
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namespace util {
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class ZipfGenerator {
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public:
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/**
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* Creates a new ZipfGenerator with the given skewness
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* skew: Desired skewness
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*/
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explicit ZipfGenerator(const double skew);
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/**
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* Returns a number from [0,this.size)
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*/
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int next();
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/**
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* Modifies the rank of the generated indexes
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*/
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void set_size(const int new_size);
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private:
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/**
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* Returns the probability (0.0,1.0) to choose a given index
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*/
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double get_probability(const int rank);
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int size;
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double skew;
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double bottom;
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};
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} // namespace util
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} // namespace xtreemfs
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#endif // CPP_INCLUDE_UTIL_ZIPF_GENERATOR_H_
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