示例：生成随机数字

函数 > 统计 > 概率分布 > 示例：生成随机数字

示例：生成随机数字

在某一区间内创建分别由均匀分布、正态分布或指数分布的随机数字组成的矢量。

均匀分布

1. 调用函数 runif 生成 n_set 个均匀分布在 low 和 high 之间的随机数字。

2. 使用函数 hist 生成具有 n_bins 个容器的均匀集的柱状图，然后计算该集的均值。

3. 绘制柱状图并显示数据集的预期均值：

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要获得新的随机数字集，请在计算选项卡的控件组中，单击计算。每次重新计算时，使用新的种子值来生成随机数字。

正态分布

1. 调用函数 rnorm 来生成 n_set 个具有正态分布 (均值为 μ 和标准差为 σ) 的随机数字。

2. 使用函数 floor、ceil、min 和 max 来计算数据集的最大值和最小值的值域，然后计算每个容器的宽度：

3. 为绘图设置水平比例：

4. 调用函数 dnorm 来计算数据集预期的正态分布 F，然后绘制具有 n_bins 个容器的正态集的柱状图。

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指数分布

1. 调用函数 rexp 以生成比率为 r 的呈指数分布的随机数字集。

2. 调用函数 dexp 来计算数据集预期的指数分布 F，然后绘制具有 n_bins 个容器的指数集的柱状图。

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3. 调用函数 pexp 和 qexp 来计算并分别绘制 x 值的累积概率分布与 p 值的逆累积概率分布。

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函数 qexp 的第一个自变量为概率且必须小于 1，因此需要将 int 除以 100。