R JSON Files

JSON: JavaScript Object Notation(JavaScript Object Notation).

JSON is a syntax for storing and exchanging text information.

JSON is similar to XML, but it is smaller, faster, and easier to parse.

If you are not familiar with JSON, you can first refer to:JSON Tutorial

To install the R JSON extension package, we can enter the following command in the R console:

install.packages("rjson", repositories = "https://mirrors.ustc.edu.cn/CRAN/")

Check if the installation is successful:

any(grepl("rjson",installed.packages()))
[1]] TRUE

Create a sites.json file, the json file is in the same directory as the test script, the code is as follows:

{　
　　　"id":["1"2"3"]
　　　"name":["Google","w3codebox","Taobao"],
　　　"url":["www.google.com","www.3codebox.com","www.taobao.com"],
　　　"likes":[　111,222,333]
}

Next, we can use the rjson package to load the data from the json file.

To view the data, use [ ] for a specific row, and use [[ ]] for a specific row and column:

# Load rjson package
library("rjson")
# Get json data
result　<-　fromJSON(file = "sites.json")
# Output the result
print(result)
print("===============")
# Output the　1　Column results
print(result[1])
print("===============")
# Output the　2　Row　2　Column results
print(result[[2]]2]])

The output of the above code is:

$id
[1]　"1"　"2"　"3"
$name
[1]　"Google"　"w3codebox"　"Taobao"
$url
[1]　"www.google.com"　"www.oldtoolbag.com"　"www.taobao.com"
$likes
[1]　111　222　333
[1]　"==============="
$id
[1]　"1"　"2"　"3"
[1]　"==============="
[1]　"w3codebox"

We can also use as.data.frame() The function can convert json file data to data frame type, which makes it easier to operate on the data:

# Load rjson package
library("rjson")
# Get json data
result　<-　fromJSON(file = "sites.json")
# Convert to data frame
json_data_frame　<-　as.data.frame(result)
print(json_data_frame)

The output of the above code is:

　　id　name　　url　likes
1　　1　Google　www.google.com　　　111
2　　2　w3codebox　www.oldtoolbag.com　　　222
3　　3　Taobao　www.taobao.com　　　333