集成類

Question

嘿這裏大家是我的代碼：

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這裏是我的集成類：

package Chapter5; 

    /*Author: Cory Zander 
    * Purpose: Find the area and volume between two curves 
    */ 
    public class Integration 
    { 

static double x; 
static double dx; 
static double f, g; 
static double sumg = 0; 
static double sumf = 0; 
public static double f(double x) 
{ 
    f = x * Math.exp(x); 
    return x; 


} 
public static double g(double x) 
{ 
    g = Math.pow(x, 2); 
    return x; 

} 

public static double Areaf(double lower, double upper) 
{ 
    int i; 
    x = lower; 
    dx = (upper - lower)/2000; 
    for(i = 0; i <= 2000; i++) 
    { 
     if(i == 0 || i == 2000) 
     { 
      sumf += f; 
     } 
     else 
     { 
      sumf += 2 * f; 
     } 
     x += dx; 


    } 
    sumf *= dx/2; 
    return sumf; 


} 
public static double Areag(double lower, double upper) 
{ 
    int i; 
    x = lower; 
    dx = (upper - lower)/2000; 
    for(i = 0; i <= 2000; i++) 
    { 
     if(i == 0 || i == 2000) 
     { 
      sumg += g; 
     } 
     else 
     { 
      sumg += 2 * g; 
     } 
     x += dx; 


    } 
    sumg *= dx/2; 
    return sumg; 
} 

好吧，我剛剛編輯這個固定的areaf和areag問題，但由於某些原因，當我得到的f曲線下的區域仍然得到0.爲什麼它沒有采取積分類的sumf

Answer 1

public static void main(String[] args){ 
    if (c == 1){ 
     //... 
     double area1 = Integration.Areaf(lower, upper); 
     double area2 = Integration.Areag(lower, upper); 
     sum = area1 - area2;//sum and minus used? 
     System.out.println("Area between the two curves = " + sum); 
    } 
} 

另外，您還錯誤地使用了繼承，導致基類（Integration）中的所有方法都是static。您可以簡單地刪除子類中的extends子句或以正確的方式進行調整。