JSON到R data.frame

Question

I have a problem using rjson package to convert JSON to R data.frame .

I started with:

library("rjson")
json_file <- "btcusd.txt"
json_data <- fromJSON(paste(readLines(json_file), collapse=""))

btcusd.txt file contains the following:

{"Response":"Success","Type":100,"Aggregated":true,"Data":
        [{"time":1510650000,"close":6488.28,"high":6618.69,"low":6482.22,"open":6492.35,"volumefrom":9422.44,"volumeto":61626698.63},
        {"time":1510671600,"close":6541,"high":6592.05,"low":6487.35,"open":6549.1,"volumefrom":12618.61,"volumeto":82634018.7},],
        "TimeTo":1511298000,"TimeFrom":1510574400,"FirstValueInArray":true,"ConversionType":{"type":"direct","conversionSymbol":""}}

Can anyone help me to make it into a data.frame?

Answer 1

I'd try jsonlite package.

Based on what you have I'd try this:

install.packages("jsonlite")
library(jsonlite)

mydata <- fromJSON("btcusd.txt")

But, I inspected your data and it's messy. Can you provide some additional information? if that comes from an API maybe it's easier to read the XML version instead.

Answer 2

There is an extra comma in your JSON input. If you remove the comma it works OK:

json_txt <- '{
    "Response": "Success",
    "Type": 100,
    "Aggregated": true,
    "Data": [{
            "time": 1510650000,
            "close": 6488.28,
            "high": 6618.69,
            "low": 6482.22,
            "open": 6492.35,
            "volumefrom": 9422.44,
            "volumeto": 61626698.63
    }, {
            "time": 1510671600,
            "close": 6541,
            "high": 6592.05,
            "low": 6487.35,
            "open": 6549.1,
            "volumefrom": 12618.61,
            "volumeto": 82634018.7
    }], 
    "TimeTo": 1511298000,
    "TimeFrom": 1510574400,
    "FirstValueInArray": true,
    "ConversionType": {
            "type": "direct",
            "conversionSymbol": ""
    }   
}'  
data.frame(fromJSON(json_txt))