将数据框列拆分为多列

Question

说我有一个看起来像这样的数据框：

gene    drug    log2FC
Ubb    Naloxone    0.6375514
Tuba1a   Naloxone    0.5827224
Scd1    Naloxone    -0.7249997
Ubb    Aspirin    0.8000
Tuba1a    Aspirin  0.73324
Scd1    Aspirin    0.2497
Ubb    Haldol    0.0375
Tuba1a    Haldol    0.25824
Scd1    Haldol    -0.0249997

是否有一种简单的方法可以为每种独特的药物创建列，所以我留下了这样的内容：

gene    Naloxone_log2FC    Asirin_Log2FC    Haldol_log2FC
Ubb     0.6375514    0.73324    0.0375
Tuba1a  ...
Scd1    ...

Thanks!

Answer 1

您可以使用较新的tidyr::spread()中的tidyr::pivot_wider()：

library(tidyr)

data <- read.table(h=T, strin=F, text="gene    drug    log2FC
Ubb    Naloxone    0.6375514
Tuba1a   Naloxone    0.5827224
Scd1    Naloxone    -0.7249997
Ubb    Aspirin    0.8000
Tuba1a    Aspirin  0.73324
Scd1    Aspirin    0.2497
Ubb    Haldol    0.0375
Tuba1a    Haldol    0.25824
Scd1    Haldol    -0.0249997")

data %>% spread(drug, log2FC)
#>     gene Aspirin     Haldol   Naloxone
#> 1   Scd1 0.24970 -0.0249997 -0.7249997
#> 2 Tuba1a 0.73324  0.2582400  0.5827224
#> 3    Ubb 0.80000  0.0375000  0.6375514

data %>% pivot_wider(names_from = "drug", values_from = log2FC)
#> # A tibble: 3 x 4
#>   gene   Naloxone Aspirin  Haldol
#>   <chr>     <dbl>   <dbl>   <dbl>
#> 1 Ubb       0.638   0.8    0.0375
#> 2 Tuba1a    0.583   0.733  0.258 
#> 3 Scd1     -0.725   0.250 -0.0250

^{由reprex package（v0.3.0）于2019-11-11创建}

Answer 2

您可以使用spread包的tidyr函数（我假设您的数据框为df）

library("tidyr")

df = spread(df, drug, log2FC)

要将“ _log2FC”附加到列名，可以使用：

for (i in 2:length(colnames(df))) {
  colnames(df)[i] = paste0(colnames(df)[i], "_log2FC")
}