如何捕获列表中的列表或目标的长度

Question

如何为我的列表“my_data”获取列表（或 obs？）的长度。 它看起来像这样：

可以使用构建示例列表

list(pk24_1.CSV = c("pk24_1.CSV", "pk24_2.CSV", "pk4.CSV", "pk6_1.CSV", 
"pk6_2.CSV", "pk6_3.CSV", "pkc.CSV", "pkc1.CSV"), pk24_2.CSV = c("pk24_1.CSV", 
"pk24_2.CSV", "pk4.CSV", "pk6_1.CSV", "pk6_2.CSV", "pk6_3.CSV", 
"pkc.CSV", "pkc1.CSV"), pk4.CSV = c("pk24_1.CSV", "pk24_2.CSV", 
"pk4.CSV", "pk6_1.CSV", "pk6_2.CSV", "pk6_3.CSV", "pkc.CSV", 
"pkc1.CSV"), pk6_1.CSV = c("pk24_1.CSV", "pk24_2.CSV", "pk4.CSV", 
"pk6_1.CSV", "pk6_2.CSV", "pk6_3.CSV", "pkc.CSV", "pkc1.CSV"), 
    pk6_2.CSV = c("pk24_1.CSV", "pk24_2.CSV", "pk4.CSV", "pk6_1.CSV", 
    "pk6_2.CSV", "pk6_3.CSV", "pkc.CSV", "pkc1.CSV"), pk6_3.CSV = c("pk24_1.CSV", 
    "pk24_2.CSV", "pk4.CSV", "pk6_1.CSV", "pk6_2.CSV", "pk6_3.CSV", 
    "pkc.CSV", "pkc1.CSV"), pkc.CSV = c("pk24_1.CSV", "pk24_2.CSV", 
    "pk4.CSV", "pk6_1.CSV", "pk6_2.CSV", "pk6_3.CSV", "pkc.CSV", 
    "pkc1.CSV"), cy1.CSV = c("cy1.CSV", "cy24.CSV", "cy6.CSV"
    ), cy24.CSV = c("cy1.CSV", "cy24.CSV", "cy6.CSV"), cy6.CSV = c("cy1.CSV", 
    "cy24.CSV", "cy6.CSV"), chem_1.CSV = c("chem.CSV", "chem_1.CSV"
    ), coag.CSV = c("coag.CSV", "coag1.CSV"), cont.CSV = c("cont.CSV", 
    "cont_1.CSV"), cont_1.CSV = c("cont.CSV", "cont_1.CSV"), 
    dov.CSV = c("dov.CSV", "dov_1.CSV"))

我尝试了很多方法，但无法让它发挥作用。 有人可以指导我吗？

我努力了

lst5<- lapply(my_data,
        function(x) data.frame(Obs = length(x[[1]])
      ))

lst5<- lapply(my_data,
        function(x) data.frame(Obs = nrow(x))
      ))

lst5<- lapply(my_data,
        function(x) data.frame(Obs = length(x)
      ))

我想得到看起来像这样的东西：

Answer 1

像这样？

lst5 = data.frame(Data = names(my_data), obs = lengths(my_data))