r - R dplyr 将表达式作为参数传递给函数
问题描述
我有一个简单的愚蠢问题,但很抱歉这么简单。
如何将算术表达式作为函数参数传递?
test_func <- function(data, myexpr){
data %>%
filter(!! myexpr)
}
mtcars %>%
test_func(myexpr = "cyl > 6")
提前致谢
解决方案
library(dplyr)
test_func <- function(data, myexpr){
data %>%
filter(eval(parse(text = myexpr)))
}
mtcars %>%
test_func(myexpr = "cyl > 6")
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