reshaping data.frame in R (gather, spread)

Question

I want to reshape iris data in R from 5 columns to 4 columns. The final output should be have columns:

1. Species
2. Part
3. Length
4. Width

The 'Part' column should include 'Petal' and 'Sepal'

The code which I tried as below gave an error "Error: Duplicate identifiers for rows"

iris_new <- iris[c(5, 1:4)] %>% 
gather(part_measure, value, -Species) %>%
separate(part_measure, c("part", "measure"), "[.]") %>%
spread(measure, value)

Please correct me, thanks in advance.

Answer 1

You just need an ID variable to uniquely identify each row.

iris_new <- iris[c(5, 1:4)] %>% 
  mutate(id = 1:nrow(iris)) %>% 
  gather(part_measure, value, -Species, -id) %>%
  separate(part_measure, c("part", "measure"), "[.]") %>%
  spread(measure, value) %>% View()