Removing Only Adjacent Duplicates in Data Frame in R

Question

I have a data frame in R that is supposed to have duplicates. However, there are some duplicates that I would need to remove. In particular, I only want to

Answer 1

You could also try

df[c(diff(as.numeric(df$x)), 1) != 0, ]

In case x is of character class (rather than factor), try

df[c(diff(as.numeric(factor(df$x))), 1) != 0, ]
#    x  y
# 1  A  1
# 2  B  2
# 3  C  3
# 4  A  4
# 5  B  5
# 6  C  6
# 7  A  7
# 9  B  9
# 10 C 10