SE filter_ by function采用多列

Question

我想过滤一个数据框,只留下基于所选列的完整案例.这很容易用NSE filter():

library(dplyr)

dd <- data.frame(
  id = 1:4,
  var1 = c(1, 2, NA, 4),
  var2 = c(1, NA, 3, 4),
  var3 = c(1, NA, NA, NA))

dd1 <- dd %>% filter(complete.cases(var1, var2))
dd1
#>   id var1 var2 var3
#> 1  1    1    1    1
#> 2  4    4    4   NA

然而,我正试图生成此操作的SE版本,我可以传递列的引用名称.

library(lazyeval)
filtered_cols <- c("var1", "var2")

dots <- interp(~complete.cases(x), .values = list(x = filtered_cols))

dd2 <- dd %>% filter_(.dots = dots)
#> Error in eval(substitute(expr), envir, enclos): incorrect length (2), expecting: 4

str(dots)
#> Class 'formula'  language ~complete.cases(c("var1", "var2"))
#> ..- attr(*, ".Environment")=<environment: R_GlobalEnv> 

不幸的是,filtered_cols它被解析为一个字符向量.如何interp()将filtered_cols多个列名称传递给complete.cases()？

Answer 1

这是uqs()为了什么,但你必须使用更新的f_interp():

library(lazyeval)
filtered_cols <- c("var1", "var2")
filtered_col_names <- lapply(filtered_cols, as.name)

dots <- f_interp(~complete.cases(uqs(filtered_col_names)))

dd2 <- dd %>% filter_(.dots = dots)