how to compare anova using data frame by row

Question

i have a df with 2 columns:

df <- read.table(text="   a  b
1   1 g1
2   7 g1
3   9 g1
4  15 g1
5  17 g1
6   3 g2
7   5 g2
8   9 g2
9  11 g2
10  7 g2", header=TRUE)

so i want to compare g1 vs g2 using the "a" columns, something like

aov(g1 ~ g2, data=df)

well it will be ok with columns, but with rows how can I do it ????

Answer 1

The tilde is read "as a function of". Your comparison is: A as a function of B, rather than what you are trying: g1 "compared to" g2. The solution is:

aov(a~b, data = df)