如何多行轉換成多列在一排中的R

Question

我有數據以這種形式

  V1 V2 

1  6  1 

2  6  5 

3  1  0 

4  1  6 

5  1 385 

6  5  4 

7  5  6 

8  5 98 

9  0  1 

10  0  2 

，我想將其轉換成

  V1 V2 V3 V4 

1  6  1  5 

2  1  0  6  385 

3  5  4  6  98 

4  0  1  2 

任何建議做成R

Answer 1

請看下面，讓我知道，如果這對你的作品：

# Data 
df <- data.frame(V1 = c(6,6,1,1,1,5,5,5,0,0), V2 = c(1,5,0,6,385,4,6,98,1,2)) 

# Splitting 
df.split <- split(df$V2, df$V1) 

# Combining 
maxLength <- max(rapply(df.split, length)) 
# initialize 
new <- list() 
z <- NULL # hold the object for length editing to include NAs 
for(i in 1:length(df.split)){ 
    z <- df.split[[i]] 
    length(z) <- maxLength 
    new[[i]] <- c(as.numeric(names(df.split))[i], z) 
} 
final <- as.data.frame(do.call(rbind,new)) 
[,1] [,2] [,3] [,4] 
[1,] 0 1 2 NA 
[2,] 1 0 6 385 
[3,] 5 4 6 98 
[4,] 6 1 5 NA 

Answer 2

這是一個dplyr/tidyr解決方案。

library(stringr) 
library(dplyr) 
library(tidyr) 

# Create test dataframe 
df <- data.frame(V1 = c(6,6,1,1,1,5,5,5,0,0), 
       V2 = c(1,5,0,6,385,4,6,98,1,2)) 

# Group data by V1 column, pasting all V2 values into one row 
df <- df %>% 
     group_by(V1) %>% 
     summarise(V2 = paste(V2, collapse = ",")) 

# Get the number of columns to separate data into 
cols <- max(str_count(df$V2, ",")) + 1 

# Set temporary column names 
cols <- paste0("col", c(1:cols)) 

# Split V2 column into multiple columns 
df <- df %>% 
     separate(V2, into = cols, sep = ",", fill = "right") 

# Rename columns 
colnames(df) <- paste0("V", c(1:ncol(df))) 

# Convert to integer 
df[] <- lapply(df, as.integer)