如何編寫使用現有的CSV文件中的CSV文件中的值

Question

我有一個CSV文件，它看起來像

name day  value 
anji  1  10 
anji  2   6 
aru  1   8 
aru  2   5 

我想我的新的CSV文件的輸出

name day1  day2 
anji 10  6 
aru  8  5 

Answer 1

你可以使用來自tidyr或reshapespread從基R.

xy <- read.table(text = "name day  value 
anji  1  10 
       anji  2   6 
       aru  1   8 
       aru  2   5", header = TRUE) 

library(tidyr) 
out <- spread(data = xy, key = day, value = value) 

# or 
out <- reshape(xy, idvar = "name", timevar = "day", direction = "wide") 

    name 1 2 
1 anji 10 6 
2 aru 8 5 

write.table(out, file = "myfile.csv", sep = ",", 
      col.names = TRUE, row.names = FALSE)