R. 将字符类型的向量转换为字符串

Question

我在将矢量类型对象转换为字符串时遇到了一些问题。

我试过了：

x <- paste(x, sep = " ", collapse = NULL) 

和各种不同类型的粘贴函数，但is.String(x) 的返回仍然是FALSE，is.vector 的返回仍然是TRUE。下面是我的代码：

bio_sentences <- sent_detect(bio) #Using openNLP to get the sentences from a bio
is.vector(bio_sentences) #Returns TRUE
sentisimo <- bio_sentences[1] #Needed as I want to do analysis sentence by sentence
sentisimo <- paste(sentisimo, sep = " ", collapse = NULL)
as.character(sentisimo) 
is.vector(sentisimo) #Returns TRUE
is.character(sentisimo) #Returns TRUE
sentisimo <- paste(bio_sentences[1], sep = "")
as.String(sentisimo)
is.String(sentisimo) #Returns FALSE
str(sentisimo) Returns chr "1st sentence of the bio"
dput(sentisimo) #Returns "Dennis Muilenburg is chairman of the board, president and chief executive officer of The Boeing Company." 

如果有人能帮我将向量的元素转换为字符串，我将不胜感激。

Answer 1

字符串（在 NLP 包的意义上定义）与 base-R 字符不同。

library(NLP)
xchar <- "abc"
xstring <- as.String("abc")

> xchar
[1] "abc"
> xstring
abc

从这里你已经可以看出 NLP 字符串和基本 R 字符的区别之一，即打印属性。 另外：

> is.character(xstring)
[1] TRUE
> is.String(xstring)
[1] TRUE
> is.character(xchar)
[1] TRUE
> is.String(xchar)
[1] FALSE

所以如果你想要一个字符串对象，你应该使用as.String 而不是as.character