Question

这是当前的数据帧结构

public class Banana : Fruit{
     public string peelDensity { get; set; }    


      //this is a sample of Default Constructor
     public Banana()
            :base()
     {
          Price = 0; //here you're setting default value to banana once it's initialized
     }
     public override void GetPrice()
    {
          //base.GetPrice(); //here you get the value from the Parent Class 
            Price = 100; // here you're setting a value for the price of Banana once you call this method;
    }
}

想要将其更改为

value.           blue         red
1                   -1.22049503   -0.62733486
2                    1.61641224   0.43102051
3                    0.09079087   0.61619844
4                    0.32325956   -0.17718356

我看到了另一个问题的问题。 Transform structure of data frame in R

Answer 1

tidyr::gather可以做到。假设数据帧被命名为df1：

library(tidyr)
df1 %>% 
  gather(color, number, -value.)

如果您希望示例中的结果按value.排序，请添加dplyr::arrange：

library(tidyr)
library(dplyr)
df1 %>% 
  gather(color, number, -value.) %>%
  arrange(value.)

Answer 2

@ d.b的评论和@neilfws的回答很棒。这是另一种方式：

library(dplyr)

df <- data.frame(
  value = c(1, 2, 3),
  blue = c(10, 30, 50),
  red = c(20, 40, 60)
)

df2 <- data.frame(
  value = rep(1:nrow(df), each = 2),
  color = rep(c("blue", "red"), nrow(df))
) %>%
  mutate(number = if_else(color == "blue", df$blue[value], df$red[value]))

更改数据框的结构

2 个答案: