R语言函数paste和paste0

设置随机抽取字母变量v1

v1 <- sample(LETTERS,10,replace=FALSE);v1
 [1] "V" "E" "S" "L" "F" "H" "O" "W" "I" "Z"

paste()中的sep=将两个或多个向量字符串分别对应连接

paste(v1,sep = " ")
 [1] "V" "E" "S" "L" "F" "H" "O" "W" "I" "Z"

paste(v1,v1,sep = "")
 [1] "VV" "EE" "SS" "LL" "FF" "HH" "OO" "WW" "II" "ZZ"

paste(v1,v1,sep = " ")
 [1] "V V" "E E" "S S" "L L" "F F" "H H" "O O" "W W" "I I" "Z Z"

paste中的collapse=将全部字符连接变为一个字符串“ ”

paste(v1,v1,collapse = "+")               ##默认sep=" "
[1] "V V+E E+S S+L L+F F+H H+O O+W W+I I+Z Z"

paste(v1,v1,sep = "",collapse = "+")
[1] "VV+EE+SS+LL+FF+HH+OO+WW+II+ZZ"

paste(v1,v1,sep = " ",collapse = "+")
[1] "V V+E E+S S+L L+F F+H H+O O+W W+I I+Z Z"

而paste0（）与paste（）的区别是无法设定sep，默认=“”每空格。

 paste0(v1,v1,collapse = "+")
[1] "VV+EE+SS+LL+FF+HH+OO+WW+II+ZZ"

联系formula公式函数，

paste(paste(v1,collapse = "+"),"a",sep  = "~")    ###带“”
[1] "V+E+S+L+F+H+O+W+I+Z~a"

formula(paste(paste(v1,collapse = "+"),"a",sep  = "~"))
V + E + S + L + F + H + O + W + I + Z ~ a

方便多变量的计算，如前期所述的doBy包分组计算平均值等。