R devel - Feb 2002 - pweibull.c (PR#1334)

Full_Name: M Welinder
Version: 1.4
OS: (src)
Submission from: (NULL) (192.5.35.38)


It seems to me that pweibull can be improved in the lower_tail=TRUE and
log_p=FALSE
case by using expm1.  Something like

-expm1(-pow(x / scale, shape)),

I think.


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>>>>> "Morten" == Morten Welinder <terra@diku.dk>
writes:
    Morten> Full_Name: M Welinder Version: 1.4 OS: (src)
    Morten> Submission from: (NULL) (192.5.35.38)


    Morten> It seems to me that pweibull can be improved in the
    Morten> lower_tail=TRUE and log_p=FALSE case by using expm1.
    Morten> Something like

    Morten> -expm1(-pow(x / scale, shape)),

yes; now that in R-devel (1.5.0 to be)
 expm1() is guaranteed to be available -- I've changed it there.

Note that this is not only for log_p=FALSE, but for both cases
of lower_tail=TRUE

Martin
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