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我必须从Beta Pert Distribution开始生成一些随机值，其中

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我正在使用https://commons.apache.org/proper/commons-math/来计算它。

import org.apache.commons.math3.distribution.BetaDistribution;

public class BetaPertSample {
    public static void main(String[] args) {
        double alpha = 3;
        double beta = 3;

        BetaDistribution betaDistribution = new BetaDistribution(alpha, beta);

        for(int i = 0; i < 10; i++){
            System.out.println(Arrays.toString(betaDistribution.sample(5)));
        }
    }
}

这是我得到的输出：

[0.15469278774304743, 0.24006832197532496, 0.6700160564372124, 0.7894630998767309, 0.2677010833216599]
[0.36056975340251546, 0.3124278049270154, 0.8658808329431393, 0.26375527172156227, 0.8555773129311253]
[0.744334606161563, 0.46750034467932317, 0.473121312112313, 0.4080913462078363, 0.5310363769431545]
[0.6139199704205458, 0.3476524835684532, 0.8281254784392859, 0.6268730007118077, 0.8098734242274822]
[0.7636797547314598, 0.762305457843508, 0.5388498173504441, 0.27341825226924754, 0.4343036591804546]
[0.47934369329716003, 0.6531112391118911, 0.6009115030757197, 0.38518464649812034, 0.41586246696133816]
[0.3089421844688092, 0.13246689875036158, 0.7021569072987267, 0.4986960314566049, 0.3658353769573018]
[0.6536741481530508, 0.40880102770023397, 0.6428905183726568, 0.9060595485315608, 0.8191084145860973]
[0.4054538607032805, 0.7515255957117897, 0.5136013862648002, 0.5561796562706204, 0.7119459715806274]
[0.5096158228805395, 0.3400939515348804, 0.7143693299785974, 0.6251738293413021, 0.5893953597814027]

生成的值似乎具有范围[0,...,1]。

如何自定义生成值的范围，比如说，[150, 3900]？

在 Excel 中，我使用BETA.INV 函数

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我可以做这样的事情来转换样本数据并在一定范围内得到结果[min,..., max]，但我希望 Apache commons-math 库中有一个合适的方法。

public static void main(String[] args) {
    double alpha = 3;
    double beta = 3;

    int min = 10;
    int max = 100;

    BetaDistribution betaDistribution = new BetaDistribution(alpha, beta);

    for(int i = 0; i < 10; i++){
        double[] sample = betaDistribution.sample(5);

        double[] sampleInRange = Arrays.stream(sample)
                .map(x -> {
                    return Precision.round(min + x * (max-min), 2);
                })
                .toArray();

        System.out.println(Arrays.toString(sampleInRange));
    }
}
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