从由符号分隔的R向量中的字符串中提取字符
嗨,我有一个R中的字符串向量,用@分隔,我想提取用@分隔的单词..示例从由符号分隔的R向量中的字符串中提取字符,r,regex,string,R,Regex,String,嗨,我有一个R中的字符串向量,用@分隔,我想提取用@分隔的单词..示例 tweets =c( " @john @tom it is wonderful ", "@neel it is awesome ", "it is awesome") 我只想要一个名称矩阵/data.frame,没有像这样的文本作为输出 X1=c("john","tom') X2 =c("neel",NA) , x3 = (NA,NA), data frame = as.data.frame(X1,X2,x3) 如何操
tweets =c( " @john @tom it is wonderful ", "@neel it is awesome ", "it is awesome")
我只想要一个名称矩阵/data.frame,没有像这样的文本作为输出
X1=c("john","tom')
X2 =c("neel",NA) , x3 = (NA,NA), data frame = as.data.frame(X1,X2,x3)
如何操作?一个
基本R
选项是使用gregexpr/regmatches
提取,然后将NA
s填充到列表中长度为的元素
lst <- regmatches(tweets, gregexpr("(?<=@)\\w+", tweets, perl = TRUE))
do.call(rbind, lapply(lst, `length<-`, max(lengths(lst))))
# [,1] [,2]
#[1,] "john" "tom"
#[2,] "neel" NA
#[3,] NA NA