57 lines
1.5 KiB
C++
57 lines
1.5 KiB
C++
/* ----------------------------------------------------------------------------
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* GTSAM Copyright 2010, Georgia Tech Research Corporation,
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* Atlanta, Georgia 30332-0415
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* All Rights Reserved
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* Authors: Frank Dellaert, et al. (see THANKS for the full author list)
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* See LICENSE for the license information
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* -------------------------------------------------------------------------- */
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/**
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* @file Sampler.cpp
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* @author Alex Cunningham
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*/
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#include <boost/random/normal_distribution.hpp>
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#include <boost/random/variate_generator.hpp>
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#include <gtsam/linear/Sampler.h>
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namespace gtsam {
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/* ************************************************************************* */
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Sampler::Sampler(const SharedDiagonal& model, int32_t seed)
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: sigmas_(model->sigmas()), generator_(static_cast<unsigned>(seed))
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{
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}
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/* ************************************************************************* */
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Sampler::Sampler(const Vector& sigmas, int32_t seed)
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: sigmas_(sigmas), generator_(static_cast<unsigned>(seed))
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{
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}
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/* ************************************************************************* */
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Vector Sampler::sample() {
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size_t d = dim();
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Vector result(d);
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for (size_t i = 0; i < d; i++) {
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double sigma = sigmas_(i);
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// handle constrained case separately
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if (sigma == 0.0) {
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result(i) = 0.0;
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} else {
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typedef boost::normal_distribution<double> Normal;
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Normal dist(0.0, sigma);
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boost::variate_generator<boost::minstd_rand&, Normal> norm(generator_, dist);
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result(i) = norm();
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}
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}
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return result;
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}
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} // \namespace gtsam
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