r语言 - JSON 解析导致数据框中出现 NA？

Question

我从YELP公共数据挑战中下载了一组JSON文件：https://www.yelp.com/dataset/challenge

它们提供 NDJSON 格式的文件。我已经能够使用

library(jsonlite)
df <- stream_in(file("file_path"))

不幸的是，仍然有一些属性列似乎是嵌套的 data.frames，如果不非常手动地创建新列，我就无法解析出来。

例：

df$attributes$BusinessParking是一个字符列，其中包含：

{'garage': False, 'street': True, 'validated': False, 'lot': False, 'valet': False}

此列中有 NA 值。我希望能够将其解析为 5 个二进制列。有没有办法做到这一点，我错过了？我是 R 的新手，但我做了一些挖掘，还没有遇到任何解决方案。

Answer 1

您可以使用$访问器运算符来重新保证列。根据Maurits Evers关于样本大小~3 Gb的评论，我基于可用的Yelp数据集JSON，business.json的数据样本创建了一个示例(见文章末尾(。此外，您需要使用paste0将Categories连接到字符向量中，以避免每个 JSON 实体出现多行记录。

嗥。R

library(jsonlite)
df <- jsonlite::fromJSON("business.json")
df$RestaurantsTakeOut <- df$attributes$RestaurantsTakeOut      
df_bp <- df$attributes$BusinessParking      
df_wh <- df$hours
df <- cbind(df, df_bp, df_wh)
df$categories <- sapply(df$categories, paste0, collapse = ", ")
df$attributes <- NULL
df$hours <- NULL
str(df)

输出：

'data.frame':   2 obs. of  26 variables:
$ business_id       : chr  "tnhfDv5Il8EaGSXZGiuQGg" "tnhfDv5Il8EaGSXZGiuQGg"
$ name              : chr  "Garaje" "Garaje"
$ neighborhood      : chr  "SoMa" "SoMa"
$ address           : chr  "475 3rd St" "475 3rd St"
$ city              : chr  "San Francisco" "San Francisco"
$ state             : chr  "CA" "CA"
$ postal code       : chr  "94107" "94107"
$ latitude          : num  37.8 37.8
$ longitude         : num  -122 -122
$ stars             : num  4.5 4.5
$ review_count      : int  1198 1198
$ is_open           : int  1 1
$ categories        : chr  "Mexican, Burgers, Gastropubs" "Mexican, Burgers, Gastropubs"
$ RestaurantsTakeOut: logi  TRUE TRUE
$ garage            : logi  FALSE FALSE
$ street            : logi  TRUE TRUE
$ validated         : logi  FALSE FALSE
$ lot               : logi  FALSE FALSE
$ valet             : logi  FALSE FALSE
$ Monday            : chr  "10:00-21:00" "10:00-21:00"
$ Tuesday           : chr  "10:00-21:00" "10:00-21:00"
$ Friday            : chr  "10:00-21:00" "10:00-21:00"
$ Wednesday         : chr  "10:00-21:00" "10:00-21:00"
$ Thursday          : chr  "10:00-21:00" "10:00-21:00"
$ Sunday            : chr  "11:00-18:00" "11:00-18:00"
$ Saturday          : chr  "10:00-21:00" "10:00-21:00"

商业.json

[{
"business_id": "tnhfDv5Il8EaGSXZGiuQGg",
"name": "Garaje",
"neighborhood": "SoMa",
"address": "475 3rd St",
"city": "San Francisco",
"state": "CA",
"postal code": "94107",
"latitude": 37.7817529521,
"longitude": -122.39612197,
"stars": 4.5,
"review_count": 1198,
"is_open": 1,
"attributes": {
"RestaurantsTakeOut": true,
"BusinessParking": {
"garage": false,
"street": true,
"validated": false,
"lot": false,
"valet": false
}
},
"categories": [
"Mexican",
"Burgers",
"Gastropubs"
],
"hours": {
"Monday": "10:00-21:00",
"Tuesday": "10:00-21:00",
"Friday": "10:00-21:00",
"Wednesday": "10:00-21:00",
"Thursday": "10:00-21:00",
"Sunday": "11:00-18:00",
"Saturday": "10:00-21:00"
}
}, 
{
"business_id": "tnhfDv5Il8EaGSXZGiuQGg",
"name": "Garaje",
"neighborhood": "SoMa",
"address": "475 3rd St",
"city": "San Francisco",
"state": "CA",
"postal code": "94107",
"latitude": 37.7817529521,
"longitude": -122.39612197,
"stars": 4.5,
"review_count": 1198,
"is_open": 1,
"attributes": {
"RestaurantsTakeOut": true,
"BusinessParking": {
"garage": false,
"street": true,
"validated": false,
"lot": false,
"valet": false
}
},
"categories": [
"Mexican",
"Burgers",
"Gastropubs"
],
"hours": {
"Monday": "10:00-21:00",
"Tuesday": "10:00-21:00",
"Friday": "10:00-21:00",
"Wednesday": "10:00-21:00",
"Thursday": "10:00-21:00",
"Sunday": "11:00-18:00",
"Saturday": "10:00-21:00"
}
}]