R code for geometric mean
gm_mean = function(x, na.rm=TRUE, zero.propagate = FALSE){
if(any(x < 0, na.rm = TRUE)){
return(NaN)
}
if(zero.propagate){
if(any(x == 0, na.rm = TRUE)){
return(0)
}
exp(mean(log(x), na.rm = na.rm))
} else {
exp(sum(log(x[x > 0]), na.rm=na.rm) / length(x))
}
}