Error in grouping dfm

[ruudfiers]

When grouping a dfm, I get an error (Error in qatd_cpp_is_grouped_numeric(as.numeric(x), group) : Invalid groups) with one docvar, while another docvar that is similar, does work. I can't figure out what the difference is and how to solve it.

[kbenoit]

Could you supply a reproducible example please, so we can replicate the problem?

[ruudfiers]

Thanks for your reply! It had to do with missing values. You can't group by a variable that has NA's, so it seems

[kbenoit]

Interesting, thanks. @koheiw I wonder if we should trap this condition.