在 R 中使用列表

Question

我在 R 中有很多这样的列表：

[[1]]
[[1]]$long_name
[1] "Ħal Għaxaq"

[[1]]$short_name
[1] "Ħal Għaxaq"

[[1]]$types
[1] "locality"  "political"


[[2]]
[[2]]$long_name
[1] "Malta"

[[2]]$short_name
[1] "MT"

[[2]]$types
[1] "country"   "political"

有时列表有超过 2 个元素。对于每个列表，我只需要“读取”列表中 $types "country" 中元素的 $long_name

Answer 1

data <- list(list(long_name = "Hal Ghaxaq", 
                  short_name = "Hal Ghaxaq", 
                  types = c("locality", "political")), 
             list(long_name = "Malta", 
                  short_name = "MT", 
                  types = c("country", "political")))
result <- data[ sapply(data, function(el) "country" %in% el$types)]