java - 使用数字数组来调整特定返回值的机会？

Question

我正在创建一个名为 getRandomLetter() 的方法，我想随机返回英文字母表中的单个字母。我希望该方法更有可能返回具有更高关联数字的字母。

我有两个数组。字母表中的每个字母都有一个字符。第二个有 double ，每个表示另一个数组中具有相同索引的字母将是我的方法返回的字母的机会。

我试图让该方法有不同的机会根据数组中的值返回不同的字母。

不幸的是，我的方法只返回 z 和 y。

如何让 getRandomLetter() 根据我为每个字母/字符指定的数字返回特定字母/字符？

我的代码示例:

public class MCVE {
    // each letter's frequency is represented in the next array by
    // the double value at the same index as the letter
    final private static char[] CharArr = "abcdefghijklmnopqrstuvwxyz".toCharArray();
    // Holds each letter's percentage-chance to be chosen
    // For Example: 0.1 is equal to 10%
    // All-together, they add up to 1.0
    final private static double[] DoubleArr = new double[] {
            0.087248322147651, 0.035722017752760335, 0.08010391859709894,
            0.05520675470881143, 0.046763368694522627, 0.018618748646893266,
            0.028144620047629357, 0.021866204806235117, 0.016020783719419788,
            0.07101104135094176, 0.06040268456375839, 0.08703182507036156,
            0.10002164970772895, 0.027711625893050443, 0.009742368478025547,
            0.021433210651656202, 0.0012989824637367395, 0.0458973803853648,
            0.07988742151980949, 0.05260878978133795, 0.0015154795410261962,
            0.022515696038103484, 0.009309374323446633, 0.0012989824637367395,
            0.011690842173630657, 0.006927906473262611};

    private static char getRandomLetter() {
        double randomDouble = ThreadLocalRandom.current().nextDouble(0.0, 1.0);

        char retVal = ' ';
        // subtract each value in DoubleArr from randomDouble until,
        // randomDouble would be < 0, then return the char that is
        // associated with that double
        for(int i = 0; i < CharArr.length; i++) {

            double subtract = DoubleArr[i];
            if (randomDouble - subtract <= 0.0)
                retVal = CharArr[i];
            else
                randomDouble -= subtract;
        }
        return retVal;
    }

    public static void main(String[] args) {
        // get a large sample of chars to test thoroughness
        char[] sampleChars = new char[1000];
        for(int i = 0; i < 1000; i++) {
            sampleChars[i] = getRandomLetter();
        }

        // print 10 characters per line
        int ct = 0;
        for(char c: sampleChars) {
            System.out.print(c + " ");
            ct++;
            if(ct == 10) {
                ct = 0;
                System.out.println();
            }
        }
    }
}

返回内容示例:

z z z z z z z z z z

z z y z z y z z z z

z z y z z z z z z z

z y z z z z z z z z

z z z z z z z z z z

z z z z z z z z y y

z z z z z z z z z z

z y z z z z z z z z

z z z z y z y z z z

Answer 1

当你得到正确答案时，你似乎没有从for循环中“跳出”。也许您的 getRandomLetter 应该更改为:

for(int i = 0; i < CharArr.length; i++) {

        double subtract = DoubleArr[i];
        if (randomDouble - subtract <= 0.0) {
             retVal = CharArr[i];
             break;
        }
        else
            randomDouble -= subtract;
    }