r - 从列表列表中提取某些元素

Question

我有一个包含多个相关性测试的输出的列表

dput(head(corr[1:2]))
list(structure(list(statistic = c(S = 1486), parameter = NULL, 
    p.value = 0.219369570345178, estimate = c(rho = 0.265810276679842), 
    null.value = c(rho = 0), alternative = "two.sided", method = "Spearman's rank correlation rho", 
    data.name = "x$theta.x and x$theta.y"), class = "htest"), 
    structure(list(statistic = c(S = 1852), parameter = NULL, 
        p.value = 0.699151237307271, estimate = c(rho = 0.0849802371541502), 
        null.value = c(rho = 0), alternative = "two.sided", method = "Spearman's rank correlation rho", 
        data.name = "x$theta.x and x$theta.y"), class = "htest"))

我想将 p.value 和估计提取到单独的数据框中。对于每个元素，我可以这样做:

corr[[1]][3]
$p.value
[1] 0.2193696

> corr[[1]][4]
$estimate
rho 
0.2658103 

但是我没有成功地尝试立即从整个列表中提取这些值。

Answer 1

我们还可以使用 magrittr 包中的 extract 函数来实现此目的:

library(purrr)

df %>% map_dfr(magrittr::extract, c("estimate", "p.value"))

# A tibble: 2 x 2
  estimate p.value
     <dbl>   <dbl>
1   0.266    0.219
2   0.0850   0.699