Question

我有一个要合并在一起的59个数据框的列表。不幸的是，由于我已经抓取了许多数据，因此数据框中的列具有不同的类。它们都具有“名称”列，其中一些采用因子形式，有些采用字符形式。我想将它们全部更改为字符形式。我尝试了以下

dts <- c("Alabama","Alaska","Arizona","Arkansas","California","Colorado","Connecticut","Delaware","Florida",
               "Georgia","Hawaii","Idaho","Illinois","Indiana","Iowa","Kansas","Kentucky","Louisiana","Maine",
               "Maryland","Massachusetts","Michigan","Minnesota","Mississippi","Missouri","Montana","Nebraska",
               "Nevada","New_Hampshire","New_Jersey","New_Mexico","New_York","North_Carolina","North_Dakota",
               "Ohio","Oklahoma","Oregon","Pennsylvania","Rhode_Island","South_Carolina","South_Dakota","Tennessee",
               "Texas","Utah","Vermont","Virginia","Washington","West_Virginia","Wisconsin","Wyoming","Federal",
               "CCJail","DC","LAJail","NOLA","NYCJail","OCJail","PhilJail","TXJail")


for(i in 1:length(dts)){
        dts[i]$Name <- as.character(dts[i]$Name)
}

但是它只给我一个错误“错误：$运算符对原子向量无效”。有谁知道一个好的解决方法？预先感谢您的帮助！

我的最终目标是跑步

dta <-dplyr::bind_rows(Alabama,Alaska,Arizona,Arkansas,California,Colorado,Connecticut,Delaware,Florida,
       Georgia,Hawaii,Idaho,Illinois,Indiana,Iowa,Kansas,Kentucky,Louisiana,Maine,
       Maryland,Massachusetts,Michigan,Minnesota,Mississippi,Missouri,Montana,Nebraska,
       Nevada,New_Hampshire,New_Jersey,New_Mexico,New_York,North_Carolina,North_Dakota,
       Ohio,Oklahoma,Oregon,Pennsylvania,Rhode_Island,South_Carolina,South_Dakota,Tennessee,
       Texas,Utah,Vermont,Virginia,Washington,West_Virginia,Wisconsin,Wyoming,Federal,CCJail,
       DC,LAJail,NOLA,NYCJail,OCJail,PhilJail,TXJail)

但是我收到错误消息“错误：无法将..1$Residents.Confirmed和..2$Residents.Confirmed结合在一起。”每个数据帧中都有许多列，而且它们经常是不同的类。如果有人有一个更好的解决方案，我也愿意接受！谢谢！

Answer 1

我们可以使用list将数据集加载到mget中（假设数据集对象已在全局环境中创建），然后使用{{1}遍历list }，更改map中“名称”列的class，并在mutate中用后缀_dfr行绑定

map

如果有许多不同的library(dplyr) library(purrr) out <- map_dfr(mget(dts), ~ .x %>% mutate(Name = as.character(Name)))列。可能是，最好将所有列都转换为单个类，然后进行绑定

class

如果out <- map_dfr(mget(dts), ~ .x %>% mutate(across(everything(), as.character))) out <- type.convert(out, as.is = TRUE)版本为dplyr，请使用< 1.0.0

mutate_all

Answer 2

d1 <- data.frame(
  Name = as.factor(c("name1", "name2")),
  Residents.Confirmed = c(0,1)
  )
d2 <- data.frame(
  Name = c("name3", "name4"),
  Residents.Confirmed = c(2,3)
)
dataframes_list <- list(d1, d2)
for(i in 1:length(dataframes_list)){
  dataframes_list[[i]]$Name <- as.character(dataframes_list[[i]]$Name)
}
bind_rows(dataframes_list)

Answer 3

Base R解决方案：

type.convert(do.call("rbind", 
        Map(function(x){data.frame(lapply(x, as.character))}, dataframes_list)))

数据感谢@ chase171：

d1 <- data.frame(
  Name = as.factor(c("name1", "name2")),
  Residents.Confirmed = c(0,1)
)
d2 <- data.frame(
  Name = c("name3", "name4"),
  Residents.Confirmed = c(2,3)
)
dataframes_list <- list(d1, d2)

跨多个数据框更改列的类别

3 个答案: