如果rbind.fill总是返回null，我如何使我的列表成为一个数据帧？

Question

我有一份清单：

myList<-list(c("Developmental Biology", " Neuroscience", " Cell Biology"
), c("Developmental Biology", " Neuroscience", " Cell Biology"
), c("Developmental Biology", " Neuroscience", " Genomics & Genetics"
), c("Developmental Biology", " Neuroscience", " Cell Biology"
), c("Developmental Biology", " Neuroscience", " Cell Biology"
), c("Developmental Biology", " Genomics & Genetics"))

我想要这个数据框架：

     [,1]                    [,2]                   [,3]                   
[1,] "Developmental Biology" " Neuroscience"        " Cell Biology"        
[2,] "Developmental Biology" " Neuroscience"        " Cell Biology"        
[3,] "Developmental Biology" " Neuroscience"        " Genomics & Genetics" 
[4,] "Developmental Biology" " Neuroscience"        " Cell Biology"        
[5,] "Developmental Biology" " Neuroscience"        " Cell Biology"        
[6,] "Developmental Biology" " Genomics & Genetics" "NA"

我本以为可以使用rbind.fill，但do.call(rbind.fill,myList)返回的是NULL。

Answer 1

函数rbind.fill只能组合数据帧。但是列表myList中的元素是字符向量。在使用rbind.fill之前，需要将它们转换为数据帧。

这样做是可行的：

library(plyr)
rbind.fill(lapply(myList, function(x) as.data.frame(t(as.matrix(x)))))

#                      V1                   V2                   V3
# 1 Developmental Biology         Neuroscience         Cell Biology
# 2 Developmental Biology         Neuroscience         Cell Biology
# 3 Developmental Biology         Neuroscience  Genomics & Genetics
# 4 Developmental Biology         Neuroscience         Cell Biology
# 5 Developmental Biology         Neuroscience         Cell Biology
# 6 Developmental Biology  Genomics & Genetics                 <NA>