Question

我想从数据帧中随机抽取1：n行，100次（即给出2000个随机数据帧）。

我可以使用sample_n函数为10个随机行执行此操作：

ran_df <- sample_n(df, 10, replace = TRUE)

但是，如何从我的数据框中为所有可能的行数（即1行，2行，3行...... 20行）执行此操作？

我的数据框如下所示：

     bird_sp plant_sp value
1  species_a  plant_a     1
2  species_a  plant_a     1
3  species_a  plant_a     1
4  species_a  plant_a     1
5  species_a  plant_a     1
6  species_a  plant_b     1
7  species_a  plant_b     1
8  species_a  plant_b     1
9  species_a  plant_b     1
10 species_a  plant_c     1
11 species_a  plant_d     1
12 species_a  plant_d     1
13 species_b  plant_d     1
14 species_b  plant_d     1
15 species_b  plant_b     1
16 species_b  plant_b     1
17 species_b  plant_b     1
18 species_b  plant_b     1
19 species_b  plant_c     1
20 species_b  plant_c     1

Answer 1

@Mickey向sample_n建议的用户lapply，然后您可以使用bind_rows包中的dplyr或do.call包中的base将列表加入数据框。

library(dplyr)
df <- read.table(text = "bird_sp plant_sp value
                 1  species_a  plant_a     1
                 2  species_a  plant_a     1
                 3  species_a  plant_a     1
                 4  species_a  plant_a     1
                 5  species_a  plant_a     1
                 6  species_a  plant_b     1
                 7  species_a  plant_b     1
                 8  species_a  plant_b     1
                 9  species_a  plant_b     1
                 10 species_a  plant_c     1
                 11 species_a  plant_d     1
                 12 species_a  plant_d     1
                 13 species_b  plant_d     1
                 14 species_b  plant_d     1
                 15 species_b  plant_b     1
                 16 species_b  plant_b     1
                 17 species_b  plant_b     1
                 18 species_b  plant_b     1
                 19 species_b  plant_c     1
                 20 species_b  plant_c     1", header = TRUE)
# Use lapply 
samples_Data <- replicate(10, lapply(1:nrow(df), function(x) sample_n(df, x, replace = T))) %>%
  bind_rows(.)

抽样不同数量的随机行

1 个答案: