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[4] Ramer–Douglas–Peucker Algorithm – Siguniang's Blog, https://siguniang.wordpress.com/2012/07/16/ramer-douglas-peucker-algorithm/
[3] TrailNote : トラックポイントを間引くアルゴリズム, https://www.trail-note.net/tech/thinout/
[6] Matsup's blog: GPSのログを間引く(折れ線を間引く), , http://matsup.blogspot.com/2011/03/gps.html
[2] 折れ線を間引く(Ramer-Douglas-Peuckerアルゴリズム) - 330k info, , https://www.330k.info/essay/oresenwomabiku/
[1] トラック間引きアルゴリズムの比較 - 330k info, , https://www.330k.info/essay/comparison_of_track_simplify_algorithms/
[5] 研39-3.4-03田中章司郎.indd - kenkyu2016390303.pdf, http://www.shojiro-tanaka.net/images/kenkyu2016390303.pdf