Assign matching values from small df to large df

Question

I have 2 data frames of unequal size and I want to map values from the smaller data frame to the larger one based on the "color" column.

df1:

Color	Value
Red	A
Blue	B
Green	C

df2:

Color	Repetition
Red	1
Green	1
Red	2
Blue	1
Blue	2
...	...

Desired output:

Color	Repetition	Value
Red	1	A
Green	1	C
Red	2	A
Blue	1	B
Blue	2	B
...	...	...

Reproducible code:

df1 <- data.frame(c("Red", "Blue", "Green"),
                  c("A", "B", "C"))
names(df1) <- c("Color", "Value")

df2 <- data.frame(c("Red", "Green", "Red", "Blue", "Blue"),
                  c(1,1,2,1,2))
names(df2) <- c("Color", "Repetition")

I've tried merge but it didn't work for me probably because they are of different sizes. I've also tried googling for this problem but have only found python solutions.

Answer 1

Another satisfactory answer could be found here.

merge(df2, df1, by = "Color", all.x=TRUE)

 Color Repetition Value
1  Blue          1     B
2  Blue          2     B
3 Green          1     C
4   Red          1     A
5   Red          2     A