将许多宽格式列表转换为长格式

Question

我想将数千个列表从宽格式转换为长格式，因为数千个列表如下所示：

   y2010 y2011 y2012 y2013 y2014 y2015 y2016 y2017 y2018 y2019 coverage_fraction
4     12    12    12    12    12    12    12    12    12    12      0.0005232538
9     12    12    12    12    12    12    12    12    12    12      0.1390771568
10    12    12    12    12    12    12    12    12    12    12      0.7728050947
. 
.
46    12    12    12    12    12    12    12    12    12    12      0.0005232538

有没有办法将 pivot_longer(-c(11) 放入函数中，例如 mapply()，将每个列表的列更改为长格式，同时保留单个列表元素？

本质上，我想使用这段代码：

lc_extract_pred <- landcover %>% 
  exact_extract(r_cells, progress = FALSE) %>% *Convert from wide to long here* %>%
  map(~ count(., landcover=value)) %>% 
  tibble(id = r_cells$id, data = .) %>% 
  unnest(data)

如果我可以 pivot_longer()，那么年份的值通常会被分配一个列名 value，因此在映射中分配 landcover=value，并将其转换为 tibble()格式。

dat_list %>% map_lgl(function(x) pivot_longer(-c(11)) )

Error in UseMethod("pivot_longer") :
no applicable method for 'pivot_longer' applied to an object of class "c('double', 'numeric')"

这是包含一行和一些列表的可重现代码：

list(c(y2010 = 1, y2011 = 1, y2012 = 1, y2013 = 1, y2014 = 1, 
y2015 = 1, y2016 = 1, y2017 = 1, y2018 = 1, y2019 = 1, coverage_fraction = -1.33003238502638
), c(y2010 = 1, y2011 = 1, y2012 = 1, y2013 = 1, y2014 = 1, y2015 = 1, 
y2016 = 1, y2017 = 1, y2018 = 1, y2019 = 1, coverage_fraction = 0.682342381930735
), c(y2010 = 1, y2011 = 1, y2012 = 1, y2013 = 1, y2014 = 1, y2015 = 1, 
y2016 = 1, y2017 = 1, y2018 = 1, y2019 = 1, coverage_fraction = -2.09817126581704
), c(y2010 = 1, y2011 = 1, y2012 = 1, y2013 = 1, y2014 = 1, y2015 = 1, 
y2016 = 1, y2017 = 1, y2018 = 1, y2019 = 1, coverage_fraction = -0.0942304747486628
), c(y2010 = 1, y2011 = 1, y2012 = 1, y2013 = 1, y2014 = 1, y2015 = 1, 
y2016 = 1, y2017 = 1, y2018 = 1, y2019 = 1, coverage_fraction = -0.944268346233405
))

Answer 1

您可以将 dat_list 和 rbind 中的每个元素转置在一起。

result <- do.call(rbind.data.frame, lapply(dat_list, t))

#  y2010 y2011 y2012 y2013 y2014 y2015 y2016 y2017 y2018 y2019 coverage_fraction
#1     1     1     1     1     1     1     1     1     1     1       -1.33003239
#2     1     1     1     1     1     1     1     1     1     1        0.68234238
#3     1     1     1     1     1     1     1     1     1     1       -2.09817127
#4     1     1     1     1     1     1     1     1     1     1       -0.09423047
#5     1     1     1     1     1     1     1     1     1     1       -0.94426835

或 purrr 的 map_df :

purrr::map_df(dat_list, ~as.data.frame(t(.x)))

将许多宽格式列表转换为长格式

convert many lists in wide format to long format

r

reshape