\[
% general purpose
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% mathematics
% general purpose
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% set theory
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% number theory
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% analysis
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% inverse trigonometric functions
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% convolution
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% derivative
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% integral
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% complex analysis
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% Discrete Fourier Transform
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% Z transform
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% linear algebra
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% vector
% unit vector
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% probability theory
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% graph theory
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% programming
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\]
はじめに
先日、面白い記事を見つけた。二重数(下記ページでは「双対数」と呼ばれているが、Wikipediaでは「二重数」)を用いると、初等的な関数($e^x,\sin x,\cos x,\log x,\dots$)の加減乗除と合成関数で作られた関数の微分係数を機械的に計算するプログラムを比較的簡単に実装できるという話。
“二重数を用いた自動微分” の続きを読む