R将数据帧转换为JSON
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R convert dataframe to JSON
提问by user1471980
I have a dataframe that I'd like to convert to json format:
我有一个数据框，我想将其转换为 json 格式：
my data frame called res1:
我的数据框称为 res1：
library(rjson)
structure(list(id = c(1, 2, 3, 4, 5), value = structure(1:5, .Label = c("server1",
"server2", "server3", "server4", "server5"), class = "factor")), .Names = c("id",
"value"), row.names = c(NA, -5L), class = "data.frame")
when I do:
当我做：
toJSON(res1)
I get this:
我明白了：
{"id":[1,2,3,4,5],"value":["server1","server2","server3","server4","server5"]}
I need this json output to be like this, any ideas?
我需要这个 json 输出是这样的，有什么想法吗？
[{"id":1,"value":"server1"},{"id":2,"value":"server2"},{"id":3,"value":"server3"},{"id":4,"value":"server4"},{"id":5,"value":"server5"}]
采纳答案by MrFlick
How about
怎么样
library(rjson)
x <- toJSON(unname(split(res1, 1:nrow(res1))))
cat(x)
# [{"id":1,"value":"server1"},{"id":2,"value":"server2"},
# {"id":3,"value":"server3"},{"id":4,"value":"server4"},
# {"id":5,"value":"server5"}]
By using split()we are essentially breaking up the large data.frame into a separate data.frame for each row. And by removing the names from the resulting list, the toJSONfunction wraps the results in an array rather than a named object.
通过使用，split()我们实质上是将大型 data.frame 分解为每行一个单独的 data.frame。通过从结果列表中删除名称，该toJSON函数将结果包装在一个数组中，而不是一个命名对象中。
回答by nycdatawrangler
The jsonlitepackage exists to address exactly this problem: "A practical and consistent mapping between JSON data and R objects."
所述jsonlite包是否存在于地址恰好此问题：“JSON数据和R对象之间的实际和一致映射”。
Its toJSONfunction provides this desired result with the default options:
它的toJSON功能通过默认选项提供了这个期望的结果：
library(jsonlite)
x <- toJSON(res1)
cat(x)
## [{"id":1,"value":"server1"},{"id":2,"value":"server2"},
## {"id":3,"value":"server3"},{"id":4,"value":"server4"},
## {"id":5,"value":"server5"}]
回答by Jared Wilber
Now you can easily just call jsonlite::write_json()directly on the dataframe.
现在您可以轻松地直接调用jsonlite::write_json()数据帧。
回答by SymbolixAU
You can also use library(jsonify)
你也可以使用 library(jsonify)
jsonify::to_json( res1 )
# [{"id":1.0,"value":"server1"},{"id":2.0,"value":"server2"},{"id":3.0,"value":"server3"},{"id":4.0,"value":"server4"},{"id":5.0,"value":"server5"}]
