从字符列中删除表达式的最干净的方法是什么？

Posted 2021-04-19

所以我有一列（species_names）包含多个名称，并且我用这些行从df中的字符中删除了多个表达式：

df$species_name<-gsub("[0-9]+.+", "", df$species_name)
df$species_name<-gsub("[a-z,A-Z]+[0-9]+.+", "", df$species_name)
df$species_name<-sub("^[A-Z,a-z] ", "", df$species_name)
df$species_name<-gsub("^[A-Z,a-z][A-Z,a-z] ", "", df$species_name)
df$species_name<-gsub(" [A-Z,a-z]$", "", df$species_name)
df$species_name<-gsub(" [A-Z,a-z][A-Z,a-z]$", "", df$species_name)
df$species_name<-gsub("[0-9]+.*", "", df$species_name)
df$species_name<-gsub("[a-z,A-Z]+[0-9]+.*", "", df$species_name)
df$species_name<-gsub("[0-9]+", "", df$species_name)
df$species_name<-gsub(" +$", "", df$species_name)
df$species_name<-gsub("-", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" sp.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" sp. nov", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" cf.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" complex.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" cmplx.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" cmplx$", "", df$species_name)
df$species_name<-gsub(" pr.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" f.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" nr.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" s.l.", "", df$species_name,fixed = TRUE)
df$species_name<-gsub(" grp.", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" [A-Z]+.+$", "", df$species_name)
df$species_name<-gsub(" type", "", df$species_name,fixed=TRUE)
df$species_name<-gsub(" group", "", df$species_name,fixed=TRUE)

有什么方法可以使此过程更简洁一些，而不需要太多行？由于此代码位于闪亮的应用程序中的函数内部，因此我想知道是否可以采用另一种更简单的方法。预先感谢您的任何回答

答案

您可以在gsub中使用Reduce：

x <- c("abca", "acde")
y <- c("a", "b")

Reduce(function(a,b) gsub(b, "", a) , y, x)
#[1] "c"   "cde"

应等于：

x <- gsub("a", "", x)
x <- gsub("b", "", x)
x
#[1] "c"   "cde"