How to combine two rows based on multiple columns in a dataframe?

Question

The title says it all, I have a large dataset that consists of factory and latitude and longitude, and among others. some of the factories I find have identical lat long although their name slightly different. How can I combine rows of factories that have the same lat-long in R?

mill	latitude	longitude	ID
a.	12.34.	7.86.	NA
A.	12.34.	7.86.	4
b	47.56.	27.07.	5.

The output I am looking for is:

mill	latitude	longitude	ID
A.	12.34.	7.86.	4
b.	47.56.	27.07.	5

Answer 1

Base R

aggregate(.~latitude+longitude,df,tail,1)

  latitude longitude mill ID
1    12.34      7.86   A.  4
2    47.56     27.07    b  5

Answer 2

We can use

library(dplyr)
df1 %>%
  arrange(latitude, longitude, is.na(ID)) %>%
  distinct(latitude, longitude, .keep_all = TRUE)