Subsetting numeric variable but not factor in R-CodePudding

I would like to calculate Linear mixed-effect models via for loop where there is always hard-coded Y and random effect. The X variables (var.nam[i]) are to be loop through. I wrote the code and it is working (as I believe), but I would also like to subset X variable (var.nam[i]) depending on the X variable (var.nam[i]) type (numeric, factor) where:

when X variable (var.nam[i]) is numeric, exclude all observation equal to 0

when X variable (var.nam[i]) is factor, do not subset X variable (var.nam[i])

A short sample of my code is here:

for(i in 1:length(var.nam)) {
        formula[i] <- paste0("Y", "~", paste0(c(var.nam[i], c("Season"), 
                                                          c("Sex"), 
                                                          c("Age"), 
                                                          c("BMI"),
                                                          c("(1|HID)")), collapse=" "))
        model <- lmer(formula[i], data = subset(data, paste0(c(var.nam[i])) != 0))
# loop continues...
}

As it is written now, it will subset all X variables (var.nam[i]) regardless of the type. Is there any workaround or different way to subset variable, that would work in this specific case?

CodePudding user response：

Checking if this solution works is a bit hard without data or the complete for loop. Based on your question you want to conditionally subset, adding a if else statement should make this possible:

for(i in 1:length(var.nam)) {
        formula[i] <- paste0("Y", "~", paste0(c(var.nam[i], c("Season"), 
                                                          c("Sex"), 
                                                          c("Age"), 
                                                          c("BMI"),
                                                          c("(1|HID)")), collapse=" "))
        data1 <- if(mode(var.nam[i]) == "numeric") {subset(data, paste0(c(var.nam[i])) !=0)} else {data} 
        model <- lmer(formula[i], data = data1)
# loop continues...
}