On 11/16/09, Ted Harding <ted.hard...@manchester.ac.uk> wrote: > Not in this case (see below), though of course in general "-" takes > precedence over "^", so, for example, in the expression > > -2^(1/3) > > the "-" is applied first, giving (-2); and then "^" is applied > next, giving (-2)^(1/3). There is a work-round (see below). > Hmm.. I may be doing something wrong, but from here it looks to be the opposite. > -2^(1/3); -(2)^(1/3); -(2^(1/3)); [1] -1.2599 [1] -1.2599 [1] -1.2599 > (-2)^(1/3) [1] NaN
The results don't change when switching from the unary minus. > 0-2^(1/3); 0-(2)^(1/3); 0-(2^(1/3)); [1] -1.2599 [1] -1.2599 [1] -1.2599 It seems to me that in this example "^" is applied first, and "-" second. There is also this fortune entry. > fortune("unary") Thomas Lumley: The precedence of ^ is higher than that of unary minus. It may be surprising, [...] Hervé Pagès: No, it's not surprising. At least to me... In the country where I grew up, I've been teached that -x^2 means -(x^2) not (-x)^2. -- Thomas Lumley and Hervé Pagès (both explaining that operator precedence is working perfectly well) R-devel (January 2006) Liviu ______________________________________________ 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.