Tidyr spread function

Question

I'm trying to spread a two column dataset into multiple columns. Here is a similar dataframe.

dummydf<- data.frame(LnPD=rnorm(25,0.6,3),K=rep(x,5))

All I want to do is reshape the data so each column is an appropriate factors (i.e. there should be 5 columns each for A:E) with corresponding figures. I thought this would do it but it keeps asking for column names:

  dummy %>% 
  group_by(K) %>%
  mutate(group_now = 1:n())
  spread(K,LnPD)

I'm sure it's a simple fix but I can't get my head around it. The other error it gave me was something related with duplicate identifiers, although that was with my own dataset not the above.

Thanks in advance.

you are missing a pipe (%>%) after your mutate call and you call dummy instead of dummydf. When I correct those issues and replace K=rep(x, 5) in your data.frame() call with K=rep(c(1, 2, 3, 4, 5),5) the code works for me — tbradley
I'll give it a go. Sorry the missing pipe and dummy only happened when I wrote script in here. btw the x is x<-factor(LETTERS[1:5]) — Dasr
Thanks guys. All good. Managed to get it sorted. Not sure what it was but seems to work after I restarted Rstudio! — Dasr

Unknown Unknown · Accepted Answer · 2018-02-14T08:46:17

As per tbradley's comment, this works for me:

library(tidyverse)

x <- factor(LETTERS[1:5])
dummydf <- data.frame(LnPD=rnorm(25,0.6,3),K=rep(x,5))

dummydf %>% 
  group_by(K) %>%
  mutate(group_now = 1:n()) %>% 
  spread(K, LnPD)

#> # A tibble: 5 x 6
#>   group_now      A     B     C       D     E
#> *     <int>  <dbl> <dbl> <dbl>   <dbl> <dbl>
#> 1         1 -0.330  4.25 2.83   1.64    1.88
#> 2         2  1.56   2.51 0.348 -6.30    1.34
#> 3         3  0.589 -5.91 2.60   9.25    2.26
#> 4         4  3.47   4.83 2.89  -0.778   2.98
#> 5         5  2.22  -3.36 2.13  -0.0230  1.19

Tidyr spread function

1 Answers