Roland Conybeare
ecd019e8bb
git-subtree-dir: xo-distribution git-subtree-mainline:4e022df686git-subtree-split:036ca5d817
57 lines
1.6 KiB
C++
57 lines
1.6 KiB
C++
/* @file Uniform.hpp */
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#pragma once
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#include "Distribution.hpp"
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namespace xo {
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namespace distribution {
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/* uniform distribution on an interval */
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class Uniform : public Distribution<double> {
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public:
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Uniform(double lo, double hi) : lo_(lo), hi_(hi) {}
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static rp<Uniform> unit() { return new Uniform(0.0, 1.0); }
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static double density_impl(double lo, double hi, double x) {
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if (x <= lo)
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return 0.0;
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if (x >= hi)
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return 0.0;
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return 1.0 / (hi - lo);
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} /*density_impl*/
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static double distr_impl(double lo, double hi, double x) {
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if (x <= lo)
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return 0.0;
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if (x >= hi)
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return 1.0;
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return (x - lo) / (hi - lo);
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} /*distr_impl*/
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double lo() const { return lo_; }
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double hi() const { return hi_; }
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double density(double x) const {
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return density_impl(this->lo_, this->hi_, x);
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} /*density*/
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double distribution(double x) const {
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return distr_impl(this->lo_, this->hi_, x);
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} /*distribution*/
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// ----- inherited from Distribution<double> -----
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virtual double cdf(double const & x) const override {
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return this->distribution(x);
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} /*cdf*/
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private:
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/* Invariant: .lo < .hi */
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double lo_ = 0.0;
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double hi_ = 1.0;
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}; /*Uniform*/
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} /*namespace distribution*/
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} /*namespace xo*/
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