Question

我有一个嵌套列表，我试图转换为数据框。我花了几个小时在这里检查解决方案，没有任何对我有用。

以下是我用来生成此示例的代码：

#library('devtools')
#install_github('blockspring/blockspring.R')
library(blockspring)
library(rjson)

comp <- blockspringRunParsed("alternative-to-search", list( 
  "query" = "Qualtrics", 
  "page_number" = NULL 
), list(
  "api_key" = "br_2884_cc148ba53e81b7b3eeaf1ac65bc539cf62fe9850"))$params

这会创建一个名为＆＃34; comp＆＃34;的列表。在我的环境中使用嵌套列表

 > str(comp)
    List of 1
     $ results:List of 25
      ..$ :List of 6
    .. ..$ icon       : chr "http://cdn.altrn.tv/icons/google-forms_53250.png?width=32&height=32&mode=crop&anchor=middlecenter"
      .. ..$ likes      : chr "29"
      .. ..$ name       : chr "Google Drive - Forms"
      .. ..$ pageLink   : chr "http://alternativeto.net/software/google-forms/"
      .. ..$ projectType: chr "Free"
      .. ..$ description: chr "Google Forms, part of Google Drive , is a tool...
    ...several more results returned.....
    ..$ :List of 6
          .. ..$ icon       : chr "http://cdn.altrn.tv/icons/webform_19004.png?width=32&height=32&mode=crop&anchor=middlecenter"
          .. ..$ likes      : chr "2"
          .. ..$ name       : chr "Webform"
          .. ..$ pageLink   : chr "http://alternativeto.net/software/webform/"
          .. ..$ projectType: chr "Freemium"
          .. ..$ description: chr "Free surveys that can go with you anywhere.    Build  ------  Make surveys crazy-fast with the Webform builder. Multiple pages,"| __truncated__
          ..$ :List of 5
          .. ..$ likes      : chr "1"
          .. ..$ name       : chr "Factile"
          .. ..$ pageLink   : chr "http://alternativeto.net/software/factile/"
          .. ..$ projectType: chr "Free"
          .. ..$ description: chr "Factile is free online survey building

我尝试过的一件事是带有data.table包的rbindlist函数

> rbindlist(comp, use.names=T, fill=T)

但我收到了这个错误：

Error in rbindlist(comp, use.names = T, fill = T) : 
  fill=TRUE, but names of input list at position 1 is NULL. All items of input list must have names set when fill=TRUE.

我也从qdap包中试过这个：

> head(mtabulate(lapply(comp, `[[`,"results")))

它返回了：

data frame with 0 columns and 1 row
Warning messages:
1: In is.na(x) : is.na() applied to non-(list or vector) of type 'NULL'
2: In is.na(x) : is.na() applied to non-(list or vector) of type 'NULL'

当我尝试将其转换为数据框时，它会创建一行df。理想情况下，数据帧将包含25行，每列6列。有些人错过了＆＃34; $ icon＆＃34; item，所以对于那些缺少价值的人来说，＆＃34; NA＆＃34;应该输入。

任何帮助都会很棒！感谢

> sessionInfo()
R version 3.1.3 (2015-03-09)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 8 x64 (build 9200)

locale:
[1] LC_COLLATE=English_United States.1252 
[2] LC_CTYPE=English_United States.1252   
[3] LC_MONETARY=English_United States.1252
[4] LC_NUMERIC=C                          
[5] LC_TIME=English_United States.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
 [1] qdap_2.2.0             RColorBrewer_1.1-2     qdapTools_1.1.0       
 [4] qdapRegex_0.2.0        qdapDictionaries_1.0.2 ggplot2_1.0.0         
 [7] data.table_1.9.4       plyr_1.8.1             rjson_0.2.15          
[10] blockspring_0.4       

loaded via a namespace (and not attached):
 [1] assertthat_0.1      bitops_1.0-6        chron_2.3-45       
 [4] colorspace_1.2-5    DBI_0.3.1           devtools_1.7.0     
 [7] digest_0.6.8        dplyr_0.4.1         gdata_2.13.3       
[10] gender_0.4.3        grid_3.1.3          gridExtra_0.9.1    
[13] gtable_0.1.2        gtools_3.4.1        httr_0.6.1         
[16] igraph_0.7.1        jsonlite_0.9.14     magrittr_1.5       
[19] MASS_7.3-39         mime_0.2            munsell_0.4.2      
[22] NLP_0.1-6           openNLP_0.2-4       openNLPdata_1.5.3-1
[25] parallel_3.1.3      plotrix_3.5-11      proto_0.3-10       
[28] R.methodsS3_1.7.0   R.oo_1.19.0         R.utils_2.0.2      
[31] Rcpp_0.11.5         RCurl_1.95-4.5      reports_0.1.4      
[34] reshape2_1.4.1      rJava_0.9-6         scales_0.2.4       
[37] slam_0.1-32         stringr_0.6.2       tcltk_3.1.3        
[40] tm_0.6              tools_3.1.3         venneuler_1.1-0    
[43] wordcloud_2.5       xlsx_0.5.7          xlsxjars_0.6.1     
[46] XML_3.98-1.1

Answer 1

您可以使用rbind.fill库中的plyr

library(plyr)
do.call(rbind.fill, lapply(unlist(comp, rec=F), as.data.frame))

将具有不同维度的嵌套列表转换为数据框

1 个答案: