[Rd] degraded performance with rank()
ggrothendieck at gmail.com
Sat May 30 20:31:18 CEST 2009
On Sat, May 30, 2009 at 10:58 AM, Tim Bergsma <timb at metrumrg.com> wrote:
> I'm maintaining a package that creates an object that is essentially a
> classed version of numeric. I updated recently from 2.7.1 to 2.9.0,
> and merges involving my class suddenly took a huge performance hit.
> I've traced the problem to something near rank(). From NEWS, it seems
> rank() etc. changed in 2.8.0. Methods for xtfrm() are supposed to
> help, but I've had no success. There was some chatter about this in
> the archives back in Sept 08 (though apparently regarding S4), with a
> suggestion that it is related to `[.` methods. That has been my
> experience. In the toy example below, the problem disappears if
> `[.my` is not defined. Under R 2.7.1 on Mac, both cat() statements
> take the same amount of time, and that time depends very little on the
> length of x. Under 2.9.0, the classed version takes much longer, and
> the time grows (more than?) exponentially with length(x).
> Is there something I can do to xtfrm.my() or [.my(), etc. to restore
> the performance?
> Thanks in advance,
> rm(...deleted rest of line...
Please don't post code like that. Someone may wipe out valuable
objects in their workspace.
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