stringr构建在stringi之上,stringr专注于最重要且最常用的字符串操作函数,而stringi提供了涵盖几乎所有可以想象的内容的全面集合。...video, cross, extra, deal, authority"
str_sub(x, 1, 2)
#> [1] "wh" "vi" "cr" "ex" "de" "au"
大多数字符串函数都使用正则表达式...[aeiou](.)")
#> [,1] [,2] [,3]
#> [1,] NA NA NA
#> [2,] "vid" "v" "d"
#> [3,] "ros" "r..." "s"
#> [4,] NA NA NA
#> [5,] "dea" "d" "a"
#> [6,] "aut" "a" "t"
str_replace(x, pattern..., replacement) 替换字符串
str_replace(x, "[aeiou]", "?")