r - 如何将 searchTwitter 结果(来自库(twitteR))转换为 data.frame？

Question

我正在将 twitter 搜索结果保存到数据库 (SQL Server) 中，但当我从 twitter 中提取搜索结果时出现错误。

如果我执行:

library(twitteR)
puppy <- as.data.frame(searchTwitter("puppy", session=getCurlHandle(),num=100))

我收到错误:

Error in as.data.frame.default(x[[i]], optional = TRUE) : 
  cannot coerce class structure("status", package = "twitteR") into a data.frame

这很重要，因为为了使用 RODBC 将其添加到使用 sqlSave 的表中，它需要是一个 data.frame。至少这是我收到的错误消息:

Error in sqlSave(localSQLServer, puppy, tablename = "puppy_staging",  : 
  should be a data frame

那么有人对如何将列表强制到 data.frame 或如何通过 RODBC 加载列表有任何建议吗？

我的最终目标是拥有一个反射(reflect) searchTwitter 返回值结构的表。这是我尝试检索和加载的示例:

library(twitteR)
puppy <- searchTwitter("puppy", session=getCurlHandle(),num=2)
str(puppy)

List of 2
 $ :Formal class 'status' [package "twitteR"] with 10 slots
  .. ..@ text        : chr "beautifull and  kc reg Beagle Mix for rehomes: This little puppy is looking for a new loving family wh... http://bit.ly/9stN7V "| __truncated__
  .. ..@ favorited   : logi FALSE
  .. ..@ replyToSN   : chr(0) 
  .. ..@ created     : chr "Wed, 16 Jun 2010 19:04:03 +0000"
  .. ..@ truncated   : logi FALSE
  .. ..@ replyToSID  : num(0) 
  .. ..@ id          : num 1.63e+10
  .. ..@ replyToUID  : num(0) 
  .. ..@ statusSource: chr "&lt;a href=&quot;http://twitterfeed.com&quot; rel=&quot;nofollow&quot;&gt;twitterfeed&lt;/a&gt;"
  .. ..@ screenName  : chr "puppy_ads"
 $ :Formal class 'status' [package "twitteR"] with 10 slots
  .. ..@ text        : chr "the cutest puppy followed me on my walk, my grandma won't let me keep it. taking it to the pound sadface"
  .. ..@ favorited   : logi FALSE
  .. ..@ replyToSN   : chr(0) 
  .. ..@ created     : chr "Wed, 16 Jun 2010 19:04:01 +0000"
  .. ..@ truncated   : logi FALSE
  .. ..@ replyToSID  : num(0) 
  .. ..@ id          : num 1.63e+10
  .. ..@ replyToUID  : num(0) 
  .. ..@ statusSource: chr "&lt;a href=&quot;http://blackberry.com/twitter&quot; rel=&quot;nofollow&quot;&gt;Twitter for BlackBerry®&lt;/a&gt;"
  .. ..@ screenName  : chr "iamsweaters"

所以我认为 puppy 的 data.frame 应该具有如下列名称:

- text
- favorited
- replytoSN
- created
- truncated
- replytoSID
- id
- replytoUID
- statusSource
- screenName

Answer 1

我使用从 http://blog.ouseful.info/2011/11/09/getting-started-with-twitter-analysis-in-r/ 找到的代码不久前:

#get data
tws<-searchTwitter('#keyword',n=10)

#make data frame
df <- do.call("rbind", lapply(tws, as.data.frame))

#write to csv file (or your RODBC code)
write.csv(df,file="twitterList.csv")