thanks. would you like a patch? (seems easy enough but I thought I'd offer) looks like library/stats/R/distn.R and nmath/rgamma.c need fixing; looks like qgamma may not check for scale<0 in C code either ...
Ben Bolker Prof Brian Ripley wrote: > On Fri, 4 Nov 2005, Ben Bolker wrote: > >> >> There's an apparent inconsistency between the >> behavior of d(pqr)gamma and other distribution >> functions for "bad" parameter values. Specifically, >> most distributions give NaN and a warning for bad >> parameters (e.g. probabilities <0 or >1). In contrast, >> d(pqr)gamma actually gives an error and stops when shape<0. >> I don't see why it has to be this way -- the internal >> C code is set up to detect shape<0 (or scale<0) and >> return NaN and a warning, and none of the other >> distribution functions in that bit of the code have >> similar behavior. >> >> It would seem more consistent (and would be more >> convenient for me -- the error-instead-of-warning >> is making me have to jump through additional hoops) >> if dgamma just returned NaN and a warning. >> >> Any thoughts? > > > No one has come up with any, so let us remove the errors in R-devel. > > Note that rgamma is not protected at C level: try rgamma(10, -2), or > (worse) rgamma(10, -20) after removing the stop() call. > ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
