Hello Bernardo, --------- If I understood your problem this script solve your problem:
q<-0.15 + c(-.1,0,.1) h<-10 + c(-.1,0,.1) 5*q*h [1] 2.475 7.500 12.625 --------- OK, this solves the simple example. But what if the example is not that simple. E.g. P = 5 * q/h Here, to get the maximum tolerances for P, we need to divide the maximum value for q by the minimum value for h, and vice versa. Is there any way to do this automatically, without thinking about every single step? There is a thing called interval arithmetic (I saw it as an Octave package) which would do something like this. I would have thought that tracking how a (measuring) error propagates through a complex calculation would be a standard problem of statistics?? In other words, I am looking for a data type which is a number with a deviation +- somehow attached to it, with binary operators that automatically knows how to handle the deviation. Thank you, Jan ______________________________________________ R-help@r-project.org 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.