首页 > 解决方案 > 根据列的唯一值从一个数据框创建数据框列表

问题描述

考虑以下数据:

myd <- dput(myd)
structure(list(group = c("g1", "g1", "g1", "g1", "g1", "g2", 
"g2", "g2", "g2", "g3", "g3", "g3", "g3", "g3"), X1 = c(0, 0, 
0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0), X2 = c(1, 1, 1, 1, 1, 0, 
0, 0, 0, 1, 0, 0, 2, 0), X3 = c(1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 
1, 1, 2, 1), X4 = c(1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 1, 2, 1), 
    X5 = c(1, 0, 0, 0, 0, 2, 2, 2, 2, 2, 0, 1, 2, 2), X6 = c(2, 
    2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 1, 2, 2), X7 = c(2, 2, 2, 2, 
    2, 2, 2, 2, 1, 1, 0, 2, 2, 2), X8 = c(1, 1, 1, 1, 1, 1, 1, 
    1, 1, 1, 1, 1, 2, 1), X9 = c(2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 
    1, 1, 0, 2), X10 = c(1, 1, 1, 1, 1, 2, 2, 2, 2, 0, 0, 2, 
    1, 2), X11 = c(2, 2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 1, 2, 2), 
    X12 = c(1, 1, 1, 1, 1, 2, 2, 2, 2, 0, 1, 0, 1, 2), X13 = c(2, 
    2, 2, 2, 2, 2, 2, 2, 2, 0, 0, 1, 0, 2), X14 = c(0, 0, 0, 
    0, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1), X15 = c(0, 0, 0, 0, 0, 
    0, 0, 0, 0, 0, 0, 1, 0, 0), X16 = c(1, 1, 0, 0, 0, 1, 1, 
    1, 1, 1, 0, 2, 1, 1), X17 = c(2, 2, 2, 2, 2, 1, 1, 1, 1, 
    1, 0, 2, 1, 1), X18 = c(2, 2, 2, 2, 2, 1, 1, 1, 1, 0, 1, 
    1, 0, 1), X19 = c(2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 1, 0, 1, 
    0), X20 = c(2, 2, 2, 2, 2, 0, 0, 0, 0, 0, 1, 1, 0, 0), X21 = c(1, 
    1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 0, 1), X22 = c(0, 0, 0, 
    0, 0, 1, 1, 1, 1, 1, 0, 2, 0, 1), X23 = c(1, 1, 1, 1, 1, 
    1, 1, 1, 1, 1, 2, 0, 1, 1), X24 = c(1, 1, 1, 1, 1, 1, 1, 
    1, 1, 1, 0, 1, 2, 1), X25 = c(0, 0, 0, 0, 0, 0, 0, 0, 0, 
    0, 1, 0, 2, 0), X26 = c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 
    0, 2, 1)), row.names = c("S1", "S2", "S3", "S4", "S5", "S6", 
"S7", "S8", "S9", "S10", "S11", "S12", "S13", "S14"), class = "data.frame")

我看起来像这样:

   group X1 X2 X3 X4
S1    g1  0  1  1  1
S2    g1  0  1  1  1
S3    g1  0  1  1  1
S4    g1  0  1  1  0
S5    g1  0  1  1  0

我想根据其唯一值为myd$group3 (g1,g2,g3) 创建一个数据框列表,因此列表的每个元素都将是 myd 数据框的子集,其唯一值为myd$group. 我知道如何使用 for 循环来做到这一点,但我认为 R 中的 for 循环很慢,如果我错了,请纠正我。因此,非常欢迎使用一些 apply 系列或 dplyr 包的解决方案。

标签: rdplyr

解决方案


我们可以使用split创建一个listof data.frames

lst1 <- split(myd, myd$group)

tidyverse,可以是

library(dplyr)
myd %>%
   group_split(group)

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