要创建一个字符串向量的频率表，我们只需要使用表函数。例如，如果我们有一个向量x，其中包含随机采样的前五个英文字母的100个值，则可以使用table(x)创建向量x的表。这将生成一个表格以及向量名称。
> x1<-sample(letters[1:4],20,replace=TRUE) > x1
输出结果
[1] "d" "d" "a" "c" "a" "a" "c" "a" "d" "c" "a" "d" "d" "b" "c" "a" "b" "c" "d" [20] "b"
> table(x1)
输出结果
x1 a b c d 6 3 5 6
> x2<-sample(letters[1:26],120,replace=TRUE) > x2
输出结果
[1] "w" "j" "p" "y" "r" "m" "y" "r" "z" "v" "p" "d" "s" "x" "j" "t" "d" "e" [19] "l" "m" "f" "p" "u" "a" "d" "y" "y" "k" "n" "i" "m" "g" "s" "e" "n" "a" [37] "w" "a" "s" "w" "n" "f" "f" "n" "s" "q" "y" "a" "h" "d" "q" "h" "g" "f" [55] "z" "e" "a" "v" "f" "a" "w" "o" "u" "c" "l" "h" "z" "o" "e" "w" "x" "t" [73] "y" "f" "q" "e" "d" "c" "l" "s" "x" "i" "i" "q" "p" "o" "v" "k" "b" "w" [91] "s" "k" "s" "l" "f" "t" "j" "u" "j" "s" "p" "w" "w" "o" "d" "x" "l" "h" [109] "u" "d" "p" "l" "h" "s" "n" "a" "o" "k" "y" "m"
> table(x2)
输出结果
x2 a b c d e f g h i j k l m n o p q r s t u v w x y z 7 1 2 7 5 7 2 5 3 4 4 6 4 5 5 6 4 2 9 3 4 3 8 4 7 3
> x3<-sample(LETTERS[1:26],150,replace=TRUE) > x3
输出结果
[1] "U" "M" "A" "J" "Q" "L" "L" "Y" "A" "Q" "P" "R" "M" "T" "U" "H" "V" "H" [19] "I" "H" "G" "D" "H" "V" "X" "K" "R" "H" "Y" "I" "L" "K" "O" "W" "Z" "K" [37] "Q" "R" "D" "E" "I" "A" "E" "U" "C" "N" "S" "R" "O" "A" "Y" "I" "E" "E" [55] "D" "F" "A" "G" "S" "Y" "B" "X" "H" "J" "O" "L" "A" "K" "D" "U" "N" "K" [73] "S" "Y" "V" "V" "X" "Q" "M" "S" "G" "L" "I" "Y" "C" "T" "N" "I" "E" "E" [91] "X" "G" "B" "Q" "D" "C" "G" "R" "P" "A" "Z" "A" "Z" "Z" "X" "G" "D" "G" [109] "T" "T" "W" "I" "N" "H" "E" "P" "M" "U" "Q" "U" "P" "S" "N" "Z" "G" "P" [127] "N" "I" "C" "H" "S" "U" "Q" "Q" "S" "T" "D" "D" "I" "S" "S" "V" "R" "Q" [145] "V" "C" "O" "B" "E" "X"
> table(x3)
输出结果
x3 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 8 3 5 8 8 1 8 8 9 2 5 5 4 6 4 5 9 6 9 5 7 6 2 6 6 5
> x4<-sample(c("India","USA","UK","Turkey"),100,replace=TRUE)
> x4输出结果
[1] "Turkey" "India" "India" "USA" "India" "Turkey" "India" "USA" [9] "India" "USA" "USA" "UK" "India" "UK" "USA" "India" [17] "Turkey" "Turkey" "USA" "India" "Turkey" "USA" "USA" "UK" [25] "USA" "Turkey" "India" "Turkey" "India" "UK" "UK" "UK" [33] "UK" "USA" "USA" "UK" "Turkey" "USA" "India" "UK" [41] "India" "India" "India" "Turkey" "USA" "India" "USA" "USA" [49] "India" "UK" "India" "UK" "USA" "Turkey" "Turkey" "USA" [57] "Turkey" "Turkey" "India" "Turkey" "Turkey" "UK" "Turkey" "USA" [65] "Turkey" "India" "Turkey" "USA" "USA" "UK" "UK" "Turkey" [73] "USA" "India" "Turkey" "Turkey" "India" "Turkey" "USA" "UK" [81] "India" "Turkey" "USA" "UK" "UK" "UK" "USA" "USA" [89] "India" "India" "Turkey" "Turkey" "USA" "Turkey" "Turkey" "UK" [97] "USA" "UK" "UK" "UK"
> table(x4)
输出结果
x4 India Turkey UK USA 24 27 22 27
> x5<-sample(c("Europe","Asia","North America","Africa","South America","Antartica","Oceania"),100,replace=TRUE)
> x5输出结果
[1] "Asia" "Oceania" "Antartica" "Antartica" [5] "South America" "Oceania" "Africa" "Africa" [9] "Europe" "Africa" "Africa" "North America" [13] "North America" "Oceania" "Antartica" "Asia" [17] "Antartica" "Europe" "Asia" "North America" [21] "South America" "Europe" "Oceania" "Oceania" [25] "Asia" "Oceania" "South America" "Antartica" [29] "Europe" "Europe" "Oceania" "Africa" [33] "Asia" "Africa" "South America" "Antartica" [37] "North America" "South America" "South America" "South America" [41] "Asia" "South America" "Europe" "South America" [45] "Asia" "North America" "Africa" "North America" [49] "North America" "South America" "North America" "Antartica" [53] "Asia" "South America" "North America" "South America" [57] "Antartica" "South America" "Asia" "North America" [61] "North America" "Oceania" "North America" "Asia" [65] "Europe" "Oceania" "Africa" "Antartica" [69] "Antartica" "Antartica" "North America" "Asia" [73] "Antartica" "Antartica" "South America" "Europe" [77] "Africa" "North America" "Asia" "Africa" [81] "Oceania" "Africa" "Europe" "Asia" [85] "North America" "Africa" "Europe" "Oceania" [89] "Asia" "Europe" "Europe" "Africa" [93] "Africa" "Antartica" "Antartica" "Africa" [97] "South America" "Oceania" "South America" "North America"
> table(x5)
输出结果
x5 Africa Antartica Asia Europe North America 15 15 14 12 16 Oceania South America 12 16