转置数据框

当名称列在其中时，您最好不要转置 data.frame - 所有数值都将转换为字符串！

这是一个将数字保留为数字的解决方案：

# first remember the names
n <- df.aree$name

# transpose all but the first column (name)
df.aree <- as.data.frame(t(df.aree[,-1]))
colnames(df.aree) <- n
df.aree$myfactor <- factor(row.names(df.aree))

str(df.aree) # Check the column types

您可以使用 data.table 库中的 transpose 函数。将 numeric 值保留为 numeric 的简单快速的解决方案。

library(data.table)

# get data
data("mtcars")

# transpose
t_mtcars <- transpose(mtcars)

# get row and colnames in order
colnames(t_mtcars) <- rownames(mtcars)
rownames(t_mtcars) <- colnames(mtcars)

df.aree <- as.data.frame(t(df.aree))
colnames(df.aree) <- df.aree[1, ]
df.aree <- df.aree[-1, ]
df.aree$myfactor <- factor(row.names(df.aree))

利用 as.matrix：

# keep the first column 
names <-  df.aree[,1]

# Transpose everything other than the first column
df.aree.T <- as.data.frame(as.matrix(t(df.aree[,-1])))

# Assign first column as the column names of the transposed dataframe
colnames(df.aree.T) <- names

使用 tidyr，可以用“pivot_longer”然后“pivot_wider”转置数据帧。

要转置广泛使用的 mtcars 数据集，您应该首先将行名转换为列（函数 rownames_to_column 创建一个名为“rowname”的新列）。

library(tidyverse)

mtcars %>% 
rownames_to_column() %>% 
pivot_longer(!rowname, names_to = "col1", values_to = "col2") %>% 
pivot_wider(names_from = "rowname", values_from = "col2")

你可以给转置矩阵取另一个名字

df.aree1 <- t(df.aree)
df.aree1 <- as.data.frame(df.aree1)