將變量從一種方法發送到另一種

Question

所以我有一個程序可以計算出年級平均值，最高年級，最低年級和沒有最低年級的平均值。因此，對於我的方法，確定沒有最低年級的新平均分數，我想使用該方法中已經找到的最低分數。

/** 
* lowestGrade() - method will return lowest grade 
* @return lowGrade 
*/ 
public static double lowestGrade(double[] grades) { 

    double lowGrade = 100.0; 

    // for loop that goes through grades array and stores 
    // first grade found as highest grade 
    for (int i = 0; i < grades.length; i++) { 

     // if statement will determine true lowest grade 
     if (grades[i] < lowGrade) { 
      lowGrade = grades[i]; 
     } 
    } 

    // Output 
    return lowGrade; 
} 

/** 
* averageWOLowGrade() - method will calculate average without lowest grade 
* @return newAverage 
*/ 
public static void averageWOLowGrade(double[] grades) { 
    double newAverage = 0; 
} 

Answer 1

如前所述before，你可以存儲在字段中的最低等級：記住

private static double min = 0.0; 

public static double lowestGrade(double[] grades) { 
    // Set min and return its value. 
    return min = DoubleStream.of(grades).min().getAsDouble(); 
} 

public static double averageWOLowGrade(double[] grades) { 
    return DoubleStream.of(grades).filter(x -> x != min) 
            .average() 
            .getAsDouble(); 
} 

熊是的執行順序的問題在這裏。我寧願計算兩次值，而不是在一個靜態變量中管理狀態。甚至更好：計算所有結果在一次運行：

public static Stats computeStats(double[] grades) { 
    double min, max; 
    min = max = grades[0]; 
    double sum = 0.0; 

    for (double grade : grades) { 
     if (grade < min) { 
      min = grade; 
     } else if (grade > max) { 
      max = grade; 
     } 
     sum += grade; 
    } 

    double avg = sum/grades.length; 
    int len = 0; 
    sum = 0.0; 

    for (double grade : grades) { 
     if (grade != min) { 
      sum += grade; 
      len++; 
     } 
    } 

    return new Stats(min, max, avg, sum/len); 
} 

static class Stats { 
    public final double min; 
    public final double max; 
    public final double avg; 
    public final double avgWithoutMin; 

    Stats(double min, double max, double avg, double avgWithoutMin) { 
     this.min = min; 
     this.max = max; 
     this.avg = avg; 
     this.avgWithoutMin = avgWithoutMin; 
    } 
}