编写循环以同时在多个列表上执行

Question

我正在尝试获取这些列表：

dim_29 <- list(c(114.49337,  20.29176, 390.74801, 592.75864))
dim_30 <- list(c(112.39257,  19.24136, 388.64721, 594.85944))
dim_31 <- list(c(112.39257,  19.24136, 402.30239, 589.60745))
dim_28 <- list(c(113.44297,  19.24136, 374.99204, 587.50665))

为此：

> dim_28 <- unlist(dim_28)
> dim_28
[1] 113.44297  19.24136 374.99204 587.50665
> dim_28 <- paste(dim_28, sep = " ", collapse = ", ")
> dim_28
[1] "113.44297, 19.24136, 374.99204, 587.50665"

通过使用循环或其他方式自动处理所有列表。我必须写什么循环来完成这个或者我应该使用 differnet 函数？任何帮助都会很棒，谢谢！

Answer 1

如果您的数据结构正确，循环很容易。您有 4 个按顺序命名的列表。每个列表包含一个向量。相反，您应该有 1 个列表，其中包含 4 个向量：

dim_list = list(
  d29 = c(114.49337,  20.29176, 390.74801, 592.75864),
  d30 = c(112.39257,  19.24136, 388.64721, 594.85944),
  d31 = c(112.39257,  19.24136, 402.30239, 589.60745),
  d28 = c(113.44297,  19.24136, 374.99204, 587.50665)
)

lapply(dim_list, paste, collapse = ", ")
# $d29
# [1] "114.49337, 20.29176, 390.74801, 592.75864"
# 
# $d30
# [1] "112.39257, 19.24136, 388.64721, 594.85944"
# 
# $d31
# [1] "112.39257, 19.24136, 402.30239, 589.60745"
# 
# $d28
# [1] "113.44297, 19.24136, 374.99204, 587.50665"

Answer 2

这是我想到的一种方法。

dim_29 <- list(c(114.49337,  20.29176, 390.74801, 592.75864))
dim_30 <- list(c(112.39257,  19.24136, 388.64721, 594.85944))
dim_31 <- list(c(112.39257,  19.24136, 402.30239, 589.60745))
dim_28 <- list(c(113.44297,  19.24136, 374.99204, 587.50665)) 

list_group = list(dim_28, dim_29, dim_30, dim_31)
output_dat = list()
for (i in 1:4){
  dat =list_group[[i]][[1]]
  output_dat[i] = paste0(dat, sep = " ", collapse = ", ")
}

希望对您有所帮助。

Answer 3

> lapply(mget(ls(pattern = "^dim_\d+")), function(x) paste(unlist(x), sep = " ", collapse = ", "))
$`dim_28`
[1] "113.44297, 19.24136, 374.99204, 587.50665"

$dim_29
[1] "114.49337, 20.29176, 390.74801, 592.75864"

$dim_30
[1] "112.39257, 19.24136, 388.64721, 594.85944"

$dim_31
[1] "112.39257, 19.24136, 402.30239, 589.60745"

编写循环以同时在多个列表上执行

Writing loops to execute on multiple lists at once

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vectorization