Calculating mean when 2 conditions need met in R

Question

I am trying to get the mean age of males and females with various health conditions from my data frame.

AgeAnalyisi$Age     num
AgeAnalyisi$Gout        logic         


        

Answer 1

You could try the aggregate function:

df <- data.frame(value=1:10, letter=rep(LETTERS[1:2], each=5), group=rep(c(1,2), times=5))
aggregate(value ~ letter * group, data=df, FUN=mean)
#  letter group value
#1      A     1     3
#2      B     1     8
#3      A     2     3
#4      B     2     8