JSON文件中的“NA”转换为NA逻辑

I have json files with data for countries. One of the files has the following data:

我有json文件包含国家/地区的数据。其中一个文件包含以下数据：

"[{\"count\":1,\"subject\":{\"name\":\"Namibia\",\"alpha2\":\"NA\"}}]"

I have the following code convert the json into a data.frame using the jsonlite package:

我有以下代码使用jsonlite包将json转换为data.frame：

df = as.data.frame(fromJSON(jsonfile), flatten=TRUE))

I was expecting a data.frame with numbers and strings:

我期待一个带有数字和字符串的data.frame：

count subject.name subject.alpha2
1      Namibia             "NA"

Instead, the NA alpha2 code is being automatically converted into NA logical, and this is what I get:

相反，NA alpha2代码自动转换为NA逻辑，这就是我得到的：

str(df)
$ count         : int 1
$ subject.name  : chr "Namibia"
$ subject.alpha2: logi NA

I want alpha2 to be a string, not logical. How do I fix this?

我希望alpha2是一个字符串，而不是逻辑。我该如何解决？

1 个解决方案

#1

That particular implementation of fromJSON (and there are three different packages with that name for a function) has a simplifyVector argument which appears to prevent the corecion:

fromJSON的特定实现（并且有三个不同的包具有该函数的名称）有一个simplifyVector参数，它似乎阻止了corecion：

 require(jsonlite)

> as.data.frame( fromJSON(test, simplifyVector=FALSE ) )
  count subject.name subject.alpha2
1     1      Namibia             NA
> str( as.data.frame( fromJSON(test, simplifyVector=FALSE ) ) )
'data.frame':   1 obs. of  3 variables:
 $ count         : int 1
 $ subject.name  : Factor w/ 1 level "Namibia": 1
 $ subject.alpha2: Factor w/ 1 level "NA": 1
> str( as.data.frame( fromJSON(test, simplifyVector=FALSE ) ,stringsAsFactors=FALSE) )
'data.frame':   1 obs. of  3 variables:
 $ count         : int 1
 $ subject.name  : chr "Namibia"
 $ subject.alpha2: chr "NA"

I tried seeing if that option worked well with the flatten argument, but was disappointed:

我试着看看这个选项是否适用于扁平化的论点，但是很失望：

> str(  fromJSON(test, simplifyVector=FALSE, flatten=TRUE) )
List of 1
 $ :List of 2
  ..$ count  : int 1
  ..$ subject:List of 2
  .. ..$ name  : chr "Namibia"
  .. ..$ alpha2: chr "NA"

#1