範例：產生亂數

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範例：產生亂數

建立在區間上各自均等分佈、常態分佈或指數分佈的亂數向量。

均勻分佈

1. 呼叫函數 runif 產生在高低之間均等分佈的 n_set 亂數。

2. 使用函數 hist 產生含有 n_bins 個柱狀的均等集合柱狀圖，然後計算此集合的均數。

3. 繪製柱狀圖並顯示數據集的預期均數：

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若要取得新的亂數集，請在「計算」標籤上，按一下「控制項」群組的「計算」。每次重新計算時，都使用新的種子值產生亂數。

常態分佈

1. 呼叫函數 rnorm 產生含有均數為 μ 且標準差為 σ 之常態分佈的 n_set 亂數。

2. 使用函數 floor、ceil、min 及 max 計算數據集值域的最小值與最大值，然後計算每個柱狀的寬度：

3. 設定繪圖的水平縮放：

4. 呼叫函數 dnorm 計算數據集的預期常態分佈 F，然後繪製含有 n_bins 個柱狀的常態集合柱狀圖。

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指數分佈

1. 呼叫函數 rexp 產生一組按機率 r 以指數方式分佈的亂數。

2. 呼叫函數 dexp 計算數據集的預期指數分佈 F，然後繪製含有 n_bins 個柱狀的指數集合柱狀圖。

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3. 呼叫函數 pexp 與 qexp 分別計算及繪製值 x 的累積機率分佈，以及值 p 的累積機率逆分佈。

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函數 qexp 的第一個引數是機率且必須小於 1，因此會將 int 除以 100。

相關主題

均等分佈

常態分佈

指數分佈

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