特定格式的打印列表

Question

我有一张有72个边框的单子。这是dput (其中只有5个)。

list(`1` = c(V1 = 7.426758, V2 = 47.398349, V3 = 7.8508356, V4 = 47.686178
), `10` = c(V1 = 7.8508356, V2 = 47.686178, V3 = 8.2749132, V4 = 47.974007
), `11` = c(V1 = 8.2749132, V2 = 47.686178, V3 = 8.6989908, V4 = 47.974007
), `12` = c(V1 = 8.6989908, V2 = 47.686178, V3 = 9.1230684, V4 = 47.974007
), `13` = c(V1 = 9.1230684, V2 = 47.686178, V3 = 9.547146, V4 = 47.974007
))

这是所需的输出：

c(7.4267580,47.3983490,7.8508356,47.6861780)

如何使用for循环在期望的输出中打印每个边界框？

Answer 1

您将通过运行

dput(lapply(your_list, unname))

但是，如果您想将字符串化的向量保存到一个新的向量中，那么有一种更直接的方法，通过toString函数。首先，下面是toString对向量所做的操作：

toString(1 : 5)
# [1] "1, 2, 3, 4, 5"

太棒了！这几乎是我们想要的，我们只需要把它放到c(…)中

paste0('c(', toString(1 : 5), ')')
# [1] "c(1, 2, 3, 4, 5)"

现在，我们需要将此操作应用于原始列表中的每个元素。vapply是这样做的：

result = vapply(your_list, \(x) paste0('c(', toString(x), ')'), character(1L))

Answer 2

以下内容将以所需格式打印列表中的每个元素：

have <- list(`1` = c(V1 = 7.426758, V2 = 47.398349, V3 = 7.8508356, V4 = 47.686178
), `10` = c(V1 = 7.8508356, V2 = 47.686178, V3 = 8.2749132, V4 = 47.974007
), `11` = c(V1 = 8.2749132, V2 = 47.686178, V3 = 8.6989908, V4 = 47.974007
), `12` = c(V1 = 8.6989908, V2 = 47.686178, V3 = 9.1230684, V4 = 47.974007
), `13` = c(V1 = 9.1230684, V2 = 47.686178, V3 = 9.547146, V4 = 47.974007
))

for (item in have) {dput(unname(item))}