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--- b:head_first_statistics:permutation_and_combination [2024/09/30 00:28] – [Arranging by individuals is different than arranging by type] hkimscil
+++ b:head_first_statistics:permutation_and_combination [2024/10/01 22:40] (current) – [e.g.] hkimscil
@@ Line 217: / Line 217: @@
 . The coach classes 3 of the players as expert shooters. What’s the probability that all 3 of these players will be on the court at the same time, if they’re chosen at random?
 </WRAP>
+<WRAP box>
+<code>
+# only combination function is available in r, choose
+# for permutation
+> choose(52,5)
+[1] 2598960
+> perm <- function(n,r) { choose(n,r)*factorial(r)}
+> perm(52, 5)
+> [1] 311875200
+</code>
+</WRAP>
 <code>
@@ Line 262: / Line 275: @@
 ## 52장의 카드 중에서 5장 고를 조합은
 factorial(52)/(factorial(5)*factorial(52-5))
-all <- factorial(52)/(factorial(5)*factorial(52-5))
+all2 <- factorial(52)/(factorial(5)*factorial(52-5))
+all2
+# or
+all <- choose(52, 5)
+all
 ## royal flush = 10, 11, 12, 13, 1 각 문양
 ## 즉, 4가지. 따라서 전체 조합 중 4가지만 해당됨