Replicate columns of data.frame or matrix n times-CodePudding

I have an n x m matrix:

M<-matrix(0,nrow=3,ncol=4)
colnames(M)<-c("apple","banana","orange","cherry")
rownames(M)<-c("squash","water","milk")

I would like to replicate the columns of the matrix 5 times such that they will unique names. e.g. apple_1, apple_2,..., apple_4,..., banana_1, banana_2 etc.

I currently convert it to a tibble and try a dplyr method:

M %>% as_tibble() %>% 
  mutate(drinks=rownames(M)) %>% 
  pivot_longer(!sid,names_to = "fruit") %>% 
  slice(rep(1:n(), each=5)) %>% 
  pivot_wider(names_from=fruit,values_from=value) %>% 
  unnest()

But because it creates non-unique columns names, it seems to remove them when I convert it back to a wide format. Any help would be much appreciated

CodePudding user response：

Because data.frame is just a list with extra attributes, you can use rep(x, each=5):

m <- matrix(0, nrow = 3, ncol = 5)
colnames(m) <- c("apple", "banana", "orange", "cherry", "pear")
rownames(m) <- c("squash", "water", "milk")

d <- as.data.frame(m)
as.data.frame(rep(d, each = 5))
#>   apple apple.1 apple.2 apple.3 apple.4 banana banana.1 banana.2 banana.3
#> 1     0       0       0       0       0      0        0        0        0
#> 2     0       0       0       0       0      0        0        0        0
#> 3     0       0       0       0       0      0        0        0        0
#>   banana.4 orange orange.1 orange.2 orange.3 orange.4 cherry cherry.1 cherry.2
#> 1        0      0        0        0        0        0      0        0        0
#> 2        0      0        0        0        0        0      0        0        0
#> 3        0      0        0        0        0        0      0        0        0
#>   cherry.3 cherry.4 pear pear.1 pear.2 pear.3 pear.4
#> 1        0        0    0      0      0      0      0
#> 2        0        0    0      0      0      0      0
#> 3        0        0    0      0      0      0      0

CodePudding user response：

simple

M <-matrix(0,nrow=3,ncol=5)
    colnames(M)<-c("apple","banana","orange","cherry","blackberry")
    rownames(M)<-c("squash","water","milk")
    

M <- as.data.frame(M)
for(col_name in colnames(M)){
  for(i in 1:5){
    M[[paste0(col_name,'_',i)]] <- M[,col_name]
  }
}

output

    apple banana orange cherry blackberry apple_1 apple_2 apple_3 apple_4 apple_5 banana_1 banana_2 banana_3 banana_4 banana_5 orange_1 orange_2 orange_3
squash     0      0      0      0          0       0       0       0       0       0        0        0        0        0        0        0        0        0
water      0      0      0      0          0       0       0       0       0       0        0        0        0        0        0        0        0        0
milk       0      0      0      0          0       0       0       0       0       0        0        0        0        0        0        0        0        0
       orange_4 orange_5 cherry_1 cherry_2 cherry_3 cherry_4 cherry_5 blackberry_1 blackberry_2 blackberry_3 blackberry_4 blackberry_5
squash        0        0        0        0        0        0        0            0            0            0            0            0
water         0        0        0        0        0        0        0            0            0            0            0            0
milk          0        0        0        0        0        0        0            0            0            0            0            0