如何根据R Data帧中的元素长度删除字符串？

Question

我有一个数据框df，它的列很少，并且包含text。我想删除所有长度小于4个字符的元素。我期望的是Expected_df。可重现的示例如下。

df<-data.frame(client=c("My Name is abcdff","Name is not right","Bangalore is getting hoter","BBa wasa school topper"),serial_numer=c(1:4))


expected_df<-data.frame(client=c("Name abcdff","Name right","Bangalore getting hoter","wasa school topper"),serial_numer=c(1:4))

这就是我尝试解决的问题

df$client<-as.character(df$client)
df$client[nchar(df$client) > 3]

Answer 1

我们可以分割字符串并计算单个单词中的字符数，并仅选择大于等于4的字符。

df$client <- sapply(strsplit(as.character(df$client), "\\s+"), function(x) 
                paste0(x[nchar(x) >= 4], collapse = " "))

df
#                   client serial_numer
#1             Name abcdff            1
#2              Name right            2
#3 Bangalore getting hoter            3
#4      wasa school topper            4