重塑数据框？

Question

我有一个看起来像这样的数据框：

X1     variables   data
2.6    X2          2.5
       X3          2.9

我怎样才能将它重塑成这样：

variables    data
X1           2.6
X2           2.5
X3           2.9

谢谢！

Answer 1

您可以使用 data.table

中的 melt

  library(data.table)#v1.9.5+
  melt(setDT(df1), id.var='variables', na.rm=TRUE, value.name='data')[
    variable!='data',  variables:= variable][,variable:=NULL][]
  #    variables data
  #1:        X1  2.6
  #2:        X2  2.5
  #3:        X3  2.9

数据

 df1 <- structure(list(X1 = c(2.6, NA), variables = c("X2", "X3"),
  data = c(2.5, 
  2.9)), .Names = c("X1", "variables", "data"), class = "data.frame", 
  row.names = c(NA, -2L))

Answer 2

first_row <- c(names(df1)[1], (df1[, 1][1]))
df1 <- df1[, 2:3 ]
df2 <- rbind(first_row, df1)

df2
#  variables data
#        X1  2.6
#        X2  2.5
#        X3  2.9

重塑数据框？

Reshaping Dataframe?

r

reshape

dataframe

数据