[R] 0 * NA = NA

Petr Klasterecky klaster at karlin.mff.cuni.cz
Mon Mar 5 16:02:06 CET 2007


Alberto Monteiro napsal(a):
> Is there any way to "force" 0 * NA to be 0 instead of NA?

No (AFAIK), and it is pretty reasonable to define it this way.
If you want to treat the NAs as zeros, use
x[is.na(x)] <- 0

Petr

> For example, suppose I have a vector with some valid values, while
> other values are NA. If I matrix-pre-multiply this by a weight 
> row vector, whose weights that correspond to the NAs are zero,
> the outcome will still be NA:
> 
> x <- c(1, NA, 1)
> wt <- c(2, 0, 1)
> wt %*% x # NA
> 
> Alberto Monteiro
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
> 

-- 
Petr Klasterecky
Dept. of Probability and Statistics
Charles University in Prague
Czech Republic



More information about the R-help mailing list