要删除字符串末尾的点和数字，我们可以使用gsub函数。它将在向量的字符串末尾搜索点和数字的模式，然后可以使用不带空格的双引号删除该模式。此后，向量将通过，如以下示例所示。
x1<−c("weds.12","red.1","the.3")
x1<−gsub("\\.[0-9]*$","",x1)
x1输出结果[1] "weds" "red" "the"
sample(c("india.32","russia.14","croatia.17","indonesia.54","japan.05"),80,replace=TRUE)
x2输出结果[1] "japan.05" "russia.14" "japan.05" "india.32" "japan.05" [6] "japan.05" "japan.05" "india.32" "croatia.17" "croatia.17" [11] "indonesia.54" "croatia.17" "indonesia.54" "russia.14" "croatia.17" [16] "russia.14" "india.32" "russia.14" "russia.14" "russia.14" [21] "japan.05" "croatia.17" "croatia.17" "russia.14" "russia.14" [26] "croatia.17" "japan.05" "russia.14" "japan.05" "indonesia.54" [31] "indonesia.54" "croatia.17" "croatia.17" "india.32" "russia.14" [36] "russia.14" "russia.14" "russia.14" "croatia.17" "indonesia.54" [41] "india.32" "india.32" "india.32" "russia.14" "croatia.17" [46] "russia.14" "croatia.17" "japan.05" "india.32" "india.32" [51] "indonesia.54" "russia.14" "indonesia.54" "croatia.17" "croatia.17" [56] "croatia.17" "croatia.17" "indonesia.54" "india.32" "croatia.17" [61] "india.32" "indonesia.54" "india.32" "russia.14" "india.32" [66] "russia.14" "russia.14" "indonesia.54" "india.32" "croatia.17" [71] "india.32" "japan.05" "croatia.17" "croatia.17" "russia.14" [76] "india.32" "russia.14" "russia.14" "indonesia.54" "croatia.17"
x2<−gsub("\\.[0−9]*$","",x2)
x2输出结果[1] "japan" "russia" "japan" "india" "japan" "japan" [7] "japan" "india" "croatia" "croatia" "indonesia" "croatia" [13] "indonesia" "russia" "croatia" "russia" "india" "russia" [19] "russia" "russia" "japan" "croatia" "croatia" "russia" [25] "russia" "croatia" "japan" "russia" "japan" "indonesia" [31] "indonesia" "croatia" "croatia" "india" "russia" "russia" [37] "russia" "russia" "croatia" "indonesia" "india" "india" [43] "india" "russia" "croatia" "russia" "croatia" "japan" [49] "india" "india" "indonesia" "russia" "indonesia" "croatia" [55] "croatia" "croatia" "croatia" "indonesia" "india" "croatia" [61] "india" "indonesia" "india" "russia" "india" "russia" [67] "russia" "indonesia" "india" "croatia" "india" "japan" [73] "croatia" "croatia" "russia" "india" "russia" "russia" [79] "indonesia" "croatia"
x3<−sample(c("hot.100","warm.78","cold.05","lukewarm.54"),80,replace=TRUE)
x3输出结果[1] "lukewarm.54" "hot.100" "warm.78" "warm.78" "hot.100" [6] "warm.78" "hot.100" "lukewarm.54" "warm.78" "warm.78" [11] "hot.100" "warm.78" "cold.05" "lukewarm.54" "hot.100" [16] "hot.100" "lukewarm.54" "lukewarm.54" "lukewarm.54" "warm.78" [21] "warm.78" "cold.05" "hot.100" "lukewarm.54" "cold.05" [26] "warm.78" "warm.78" "lukewarm.54" "lukewarm.54" "cold.05" [31] "cold.05" "warm.78" "lukewarm.54" "cold.05" "cold.05" [36] "warm.78" "hot.100" "lukewarm.54" "cold.05" "cold.05" [41] "hot.100" "warm.78" "lukewarm.54" "lukewarm.54" "lukewarm.54" [46] "lukewarm.54" "lukewarm.54" "warm.78" "hot.100" "lukewarm.54" [51] "lukewarm.54" "lukewarm.54" "lukewarm.54" "cold.05" "cold.05" [56] "lukewarm.54" "warm.78" "cold.05" "hot.100" "cold.05" [61] "warm.78" "lukewarm.54" "warm.78" "cold.05" "lukewarm.54" [66] "lukewarm.54" "hot.100" "hot.100" "cold.05" "lukewarm.54" [71] "cold.05" "lukewarm.54" "warm.78" "cold.05" "cold.05" [76] "warm.78" "lukewarm.54" "cold.05" "warm.78" "cold.05"
x3<−gsub("\\.[0−9]*$","",x3)
x3输出结果[1] "lukewarm" "hot" "warm" "warm" "hot" "warm" [7] "hot" "lukewarm" "warm" "warm" "hot" "warm" [13] "cold" "lukewarm" "hot" "hot" "lukewarm" "lukewarm" [19] "lukewarm" "warm" "warm" "cold" "hot" "lukewarm" [25] "cold" "warm" "warm" "lukewarm" "lukewarm" "cold" [31] "cold" "warm" "lukewarm" "cold" "cold" "warm" [37] "hot" "lukewarm" "cold" "cold" "hot" "warm" [43] "lukewarm" "lukewarm" "lukewarm" "lukewarm" "lukewarm" "warm" [49] "hot" "lukewarm" "lukewarm" "lukewarm" "lukewarm" "cold" [55] "cold" "lukewarm" "warm" "cold" "hot" "cold" [61] "warm" "lukewarm" "warm" "cold" "lukewarm" "lukewarm" [67] "hot" "hot" "cold" "lukewarm" "cold" "lukewarm" [73] "warm" "cold" "cold" "warm" "lukewarm" "cold" [79] "warm" "cold"
x4<−sample(c("Male.1","Female.2"),80,replace=TRUE)
x4输出结果[1] "Female.2" "Male.1" "Male.1" "Male.1" "Male.1" "Female.2" [7] "Male.1" "Male.1" "Female.2" "Male.1" "Female.2" "Female.2" [13] "Male.1" "Female.2" "Female.2" "Female.2" "Male.1" "Female.2" [19] "Male.1" "Male.1" "Male.1" "Female.2" "Female.2" "Female.2" [25] "Female.2" "Female.2" "Male.1" "Female.2" "Male.1" "Female.2" [31] "Female.2" "Male.1" "Female.2" "Male.1" "Male.1" "Male.1" [37] "Female.2" "Female.2" "Female.2" "Female.2" "Female.2" "Female.2" [43] "Male.1" "Female.2" "Female.2" "Male.1" "Male.1" "Female.2" [49] "Female.2" "Female.2" "Female.2" "Female.2" "Male.1" "Female.2" [55] "Female.2" "Female.2" "Female.2" "Female.2" "Male.1" "Female.2" [61] "Female.2" "Female.2" "Male.1" "Male.1" "Female.2" "Male.1" [67] "Male.1" "Female.2" "Male.1" "Male.1" "Female.2" "Male.1" [73] "Female.2" "Male.1" "Female.2" "Female.2" "Male.1" "Male.1" [79] "Female.2" "Male.1"
x4<−gsub("\\.[0−9]*$","",x4)
x4输出结果[1] "Female" "Male" "Male" "Male" "Male" "Female" "Male" "Male" [9] "Female" "Male" "Female" "Female" "Male" "Female" "Female" "Female" [17] "Male" "Female" "Male" "Male" "Male" "Female" "Female" "Female" [25] "Female" "Female" "Male" "Female" "Male" "Female" "Female" "Male" [33] "Female" "Male" "Male" "Male" "Female" "Female" "Female" "Female" [41] "Female" "Female" "Male" "Female" "Female" "Male" "Male" "Female" [49] "Female" "Female" "Female" "Female" "Male" "Female" "Female" "Female" [57] "Female" "Female" "Male" "Female" "Female" "Female" "Male" "Male" [65] "Female" "Male" "Male" "Female" "Male" "Male" "Female" "Male" [73] "Female" "Male" "Female" "Female" "Male" "Male" "Female" "Male"