我的目标是计算从用户输入中获得的10个数字的标准偏差和。使用循环查找平均值和标准差
我只学到了,而我的班级里有。
问题: 我如何分配给每个用户输入(环内),以一个独立的变量,到后来比较平均,发现标准偏差?
(我还没有在我的课教给数组。所以,我必须解决这个问题,而无需使用数组)
我做的程序很长的一个单调乏味的方式,但如果能提供更多的代码需要显示我可以做while循环找到意思。
import java.util.Scanner;
public class StandardDev
{
public static void main (String[] args)
{
Scanner input = new Scanner (System.in);
double num1 = 0, num2 = 0, num3 = 0, num4 = 0, num5 = 0, num6 = 0, num7 = 0, num8 = 0, num9 = 0, num10 = 0, total = 0, mean = 0, stDev1 = 0, stDev2 = 0, sum = 0;
System.out.println("Enter 10 numbers: ");
num1 = input.nextDouble();
num2 = input.nextDouble();
num3 = input.nextDouble();
num4 = input.nextDouble();
num5 = input.nextDouble();
num6 = input.nextDouble();
num7 = input.nextDouble();
num8 = input.nextDouble();
num9 = input.nextDouble();
num10 = input.nextDouble();
sum = num1+num2+num3+num4+num5+num6+num7+num8+num9+num10;
mean = sum/(double) 10;
stDev1 = Math.pow(num1 - mean, 2) + Math.pow(num2 - mean, 2) + Math.pow(num3 - mean, 2) + Math.pow(num4 - mean, 2) + Math.pow(num5 - mean, 2) +
Math.pow(num6 - mean, 2) + Math.pow(num7 - mean, 2) + Math.pow(num8 - mean, 2) + Math.pow(num9 - mean, 2) + Math.pow(num10 - mean, 2);
stDev2 = Math.sqrt(stDev1/10);
System.out.println ("The mean is " + mean + ".");
System.out.println ("The standard deviation is " + stDev2 + ".");
}
}
这是我找到的意思。我的逻辑告诉我,我只能找到标准差,如果我可以单独访问这些输入从平均值和平方中减去。不知道如何,但..
import java.util.Scanner;
public class JTillman03_45
{
public static void main (String[] args)
{
Scanner input = new Scanner (System.in);
int count = 0, total = 0;
double mean, stDev = 0;
System.out.println("Enter a digit: ");
int number = input.nextInt();
while (count < 9){
total += number;
count++;
System.out.println("Enter a digit: ");
number = input.nextInt();
}
mean = total/(double) count;
System.out.println("The mean of those numbers is: " + mean);
System.out.println("The standard deviation of those numbers is: " + stDev);
}
}
阵列将很好地在这里工作。你知道是否可以使用一个? –
它只是使用循环。我修改了这个程序,并更新了下面的代码 –
添加代码示例 – khuderm