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JavaScriptで正方行列の行列式を計算する

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以下の行列Aがある時、

A = 
\begin{matrix}
a & b & c\\ 
d & e & f\\
g & h & i
\end{matrix}

行列式はこう計算出来る。

\begin{vmatrix}
A
\end{vmatrix}
=
\begin{vmatrix}
a & b & c\\ 
d & e & f\\
g & h & i
\end{vmatrix}
=
a\times
\begin{vmatrix}
e & f\\
h & i
\end{vmatrix}
- b\times
\begin{vmatrix}
d & f\\
g & i
\end{vmatrix}
+ c\times
\begin{vmatrix}
d & e\\
g & h
\end{vmatrix}

JavaScriptで実装してみるとこうなった。

function determinant(m) {
  if(m.length === 0) return 1;
  let x = 0;
  for(let ic = 0; ic < m[0].length; ic++) {
    let ans = m.slice(1).map(row => row.filter((_, index) => index !== ic));
    x += ((-1) ** ic) * m[0][ic] * determinant(ans);
  }
  return x;
};

for文をもっと宣言的に書けそう。。。

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