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hans jablonsky
Asked: 2024-04-29 09:13:17 +0800 CST

有没有办法将paste0函数与列表组合？

  • 772

我有一个名字向量：

names <- c("a", "b", "c", "d", "e", "f", "g", "h")

我想分别将这些名称与这些数字进行一系列组合：

numbers <- c(0, 0:2, 0:3, 0:1, 0:1, 0, 0, 0)

所以我的组合是：

a0 b0 b1 b2 c0 c1 c2 c3 d0 d1 e0 e1 f0 g0 h0

我该怎么做？我宁愿使用向量化函数而不是迭代。

我尝试了这些代码，但得到了错误的结果（可能是由于回收或其他原因）：

paste0(names, numbers, recycle0 = F)
paste0(names, numbers, recycle0 = T)
paste0(names, numbers |> as.list())
purrr::map_chr(names, paste0(c(0, 0:2, 0:3, 0:1, 0:1, 0, 0, 0)))

还有一些我记不太清楚了。

3 个回答

  1. Best Answer

    1) Thecumsum(...)是名称的索引，即 1 2 2 2 3 3 3 3 4 4 5 5 6 7 8，因此索引到names并粘贴numbers到末尾。不使用任何外部包。

    paste0(names[cumsum(numbers == 0)], numbers)
## [1] "a0" "b0" "b1" "b2" "c0" "c1" "c2" "c3" "d0" "d1" "e0" "e1" "f0" "g0" "h0"

    2)第二种方法也基于cumsum(...)，是使用rle来获取游程长度，将每个名称重复一定次数，然后粘贴到数字上。这也不使用任何包。

    paste0(rep(names, rle(cumsum(numbers == 0))$lengths), numbers)
## [1] "a0" "b0" "b1" "b2" "c0" "c1" "c2" "c3" "d0" "d1" "e0" "e1" "f0" "g0" "h0"

    3）这个没有使用，cumsum但它确实使用了一个包。将numbers0 替换为名称，将其他数字替换为 NA。然后用于na.locf0填写 NA 并粘贴到数字上。

    library(zoo)

paste0(na.locf0(replace(NA * numbers, numbers == 0, names)), numbers)
## [1] "a0" "b0" "b1" "b2" "c0" "c1" "c2" "c3" "d0" "d1" "e0" "e1" "f0" "g0" "h0"

    笔记

    从问题输入

    names <- c("a", "b", "c", "d", "e", "f", "g", "h")
numbers <- c(0, 0:2, 0:3, 0:1, 0:1, 0, 0, 0)
    • 5

  2. numbers这里使用作为具有最大序列的向量的解决方案

    names <- c("a", "b", "c", "d", "e", "f", "g", "h")

numbers <- c(0, 2, 3, 1, 1, 0, 0, 0)

library(purrr)

unlist(map2(.x = names,.y = numbers,.f = \(.x,.y) paste0(.x,0:.y)))

[1] "a0" "b0" "b1" "b2" "c0" "c1" "c2" "c3" "d0" "d1" "e0" "e1" "f0" "g0" "h0"
    • 2

  3. 你可以使用mapply：

    names <- c("a", "b", "c", "d", "e", "f", "g", "h")
numbers <- list(0, 0:2, 0:3, 0:1, 0:1, 0, 0, 0)
unlist(mapply(function(name, nums) paste0(name, nums), names, numbers))

    输出：

       a   b1   b2   b3   c1   c2   c3   c4   d1   d2   e1   e2    f    g    h 
"a0" "b0" "b1" "b2" "c0" "c1" "c2" "c3" "d0" "d1" "e0" "e1" "f0" "g0" "h0"
    • 2

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