list 如何将列表输出到R中的文件
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How to output a list to file in R
提问by Thomas Lee
Assume having a list of books with authors , after reading the data into a list "LS" I tried to enter it into a file and the output was
假设有一个带有作者的书籍列表，在将数据读入列表“LS”后，我尝试将其输入到文件中，输出为
> write.table(LS, "output.txt")
Error in data.frame(..., title = NULL, :
arguments imply differing number of rows: 1, 0
> write(LS, "output.txt")
Error in cat(list(...), file, sep, fill, labels, append) :
argument 1 (type 'list') cannot be handled by 'cat'
I was able to use dput but I would like the data to be formatted well (no redundancy of repeated keywords all over the file). Any suggestions? Thanks
我能够使用 dput 但我希望数据格式正确（整个文件中没有重复关键字的冗余）。有什么建议？谢谢
UPDATEdput( head (LS, 2))
更新dput( 头 (LS, 2))
list(structure(list( title = "Book 1",
authors = list(structure(c("Pooja", "Garg"),
.Names = c("forename","surname")),
structure(c("Renu", "Rastogi"),
.Names = c("forename","surname")))),
.Names = c("title", "authors")),
structure(list( title = "Book 2",
authors = list(structure(c("Barry", "Smit"), .Names = c("forename",
"surname")), structure(c("Tom", "Johnston"), .Names = c("forename",
"surname")))), .Names = c("title", "authors")))
采纳答案by Ali
You may first convert your list to a data frame:
您可以先将列表转换为数据框：
LS.df = as.data.frame(do.call(rbind, LS))
Or
或者
LS.df = as.data.frame(do.call(cbind, LS))
Then you can simply save LS.df with write.csv or write.table
然后你可以简单地用 write.csv 或 write.table 保存 LS.df
回答by mnel
Using the data you provided and rjson
使用您提供的数据和 rjson
library(rjson)
# write them to a file
cat(toJSON(LS), file = 'LS.json')
LS2 <- fromJSON('LS.json')
# some rearranging to get authors back to being a data.frame
LS3 <- lapply(LS2, function(x) { x[['authors']] <- lapply(x[['authors']], unlist); x})
identical(LS, LS3)
## TRUE
The file looks like
该文件看起来像
[{"title":"Book 1","authors":[{"forename":"Pooja","surname":"Garg"},{"forename":"Renu","surname":"Rastogi"}]},{"title":"Book 2","authors":[{"forename":"Barry","surname":"Smit"},{"forename":"Tom","surname":"Johnston"}]}]
if you want each book on a separate line then you can use
如果您希望每本书都在单独的一行上，那么您可以使用
.json <- lapply(LS, toJSON)
# add new lines and braces
.json2 <- paste0('[\n', paste0(.json, collapse = ', \n'), '\n]')
cat(.json)
[
{"title":"Book 1","authors":[{"forename":"Pooja","surname":"Garg"},{"forename":"Renu","surname":"Rastogi"}]},
{"title":"Book 2","authors":[{"forename":"Barry","surname":"Smit"},{"forename":"Tom","surname":"Johnston"}]}
]
回答by Raimi bin Karim
I use the RJSONIO package.
我使用 RJSONIO 包。
library(RJSONIO)
exportJSON <- toJSON(LS)
write(exportJSON,"LS.json")
回答by Shahryar
It's better to use format()
最好使用 format()
LS.str <- format(LS)
LS.str <- format(LS)
