回答編集履歴
1
ソースコードの改良 (aの平方根を求めたい!!)
test
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@@ -55,3 +55,73 @@
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}
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```
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(追記)
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61
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aの平方根を求めるときのソースとなります。(入力)
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```Java
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66
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import java.util.Scanner;
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import java.math.BigDecimal;
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70
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public class Sum {
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public static void main(String[] args) {
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Scanner sc = new Scanner(System.in);
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String line = sc.nextLine();
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Double n = Double.parseDouble(line);
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BigDecimal a = new BigDecimal(n); //√aを求めたい
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BigDecimal x = new BigDecimal("2.0");
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BigDecimal delta = new BigDecimal("1.0");
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BigDecimal sisu = new BigDecimal("1.0E-16");
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int count = 0;
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while (sisu.compareTo(delta) < 0) {
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BigDecimal f = x.multiply(x).subtract(a);
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BigDecimal df = x.multiply(new BigDecimal("2.0"));
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x = x.subtract(f.divide((df),BigDecimal.ROUND_HALF_UP));
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delta = (x.multiply(x).subtract(a)).abs();
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count++;
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System.out.println(count + "回目 誤差=" + delta);
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}
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System.out.println("x = " + x);
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System.out.println("x * x = " + x.multiply(x));
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}
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}
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```
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