回答編集履歴
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javaで書き直し
test
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@@ -5,6 +5,90 @@
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解: 1.4142156862745099 (計算回数: 4 )
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※上記コードを参考にjavaで書き直し
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```java
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public class memo_qa149182 {
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// 解を求める関数
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private static double f(double x) {
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return x * x - 2.0;
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}
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// 導関数
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private static double df(double x) {
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return 2.0 * x;
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}
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// ニュートン法
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private static double[] newton_method(double a, double eps) {
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int i = 0;
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for (i = 1; i < 1000; i++) {
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//漸化式
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double ah = a - f(a) / df(a);
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// 収束条件(近似解の変化が十分小さい)を満たせば計算終了
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if (Math.abs(ah - a) < eps) {
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break;
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}
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// 近似解の更新
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a = ah;
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}
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double[] result = new double[2];
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result[0] = a;
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result[1] = i * 1.0;
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return result;
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}
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public static void main(String[] args) {
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double[] ans = newton_method(1.0, 0.0001);
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System.out.printf("解:%s (計算回数:%s)%n", ans[0], (int) ans[1]);
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// 解:1.4142156862745099 (計算回数:4)
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}
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}
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```
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```Python3
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