扩展/分解 R 中的 for 循环

Question

`y <- c()

for( position in c("cannon","jackson","benford","paws","moxie") ) {
n <- nchar(position)
y[position] <- letters[n]
}

y

n

我实际上想做的是编写这个 for 循环背后的代码，但我遇到了关于去哪里使用它的问题。这个 for 循环展开后会是什么样子？

Answer 1

1. position <- "cannon"

   • n <- nchar(position) → n <- nchar("cannon") → n <- 6
   • y[position] <- letters[n] → y["cannon"] <- letters[6] → j["cannon"] <- "f"

2. position <- "jackson"

   • n <- nchar(position) → n <- nchar("jackson") → n <- 7
   • y[position] <- letters[n] → y["jackson"] <- letters[7] → j["jackson"] <- "g"

等