Is there an R function to collate row values and then convert into columns?-CodePudding

I want to rearrange my dataset by aggregating similar species and site, while converting them into a format like this below.

>
Species Value  Site
A         1      D
A         2      D
B         3      E
B         4      E
C         1      F
C         2      F

into

>
Species D  E  F
A       3  1  0                 
B       0  7  0    
C       0  0  3

Any help would be greatly appreciated. Sorry if the formatting is weird as this is my first time asking. Thank you in advance!

CodePudding user response：

Try this

xtabs(Value ~ Species   Site , data = df)

Output

       Site
Species D E F
      A 3 0 0
      B 0 7 0
      C 0 0 3

CodePudding user response：

df %>% 
  group_by(Species, Site) %>%  
  summarise(sum = sum(Value)) %>%  
  pivot_wider(names_from = Site, 
              values_from = sum, 
              values_fill = 0)

# A tibble: 3 x 4
# Groups:   Species [3]
  Species     D     E     F
  <chr>   <dbl> <dbl> <dbl>
1 A           3     0     0
2 B           0     7     0
3 C           0     0     3