[Rcpp-devel] trans() changed in latest RcppArmadillo

Savitsky, Terrance savitsky at rand.org
Mon May 30 21:02:13 CEST 2011

Dr. Sanderson, I've been able to verify that my issue resides in the
inv() function (that I typically apply to small p x p matrices, where p
= 3 - 10).  In particular, the new version/algorithm induces numerical
instability.  I've not yet tested that the results of the inv()
computation are generally accurate, only that they are not numerically
robust in comparison to 0.2.19.  I'm up against a deadline, so I
switched back to 0.2.19, which resolves my problem, for now, but will
provide a reproducible example when finished with my work.


-----Original Message-----
From: Conrad Sand [mailto:conradsand.rcpp at gmail.com] 
Sent: Monday, May 30, 2011 6:34 AM
To: rcpp-devel at r-forge.wu-wien.ac.at
Cc: Savitsky, Terrance
Subject: Re: trans() changed in latest RcppArmadillo

On 30 May 2011, Terrance Savitsky wrote:
> Hello, After upgrading to the 0.2.21 release of RcppArmadillo, my
> previously working code (across many functions) ceased working (on a
> Windows XP installation).  I re-installed the previous version
> from CRAN (via a server location not yet updated to 0.2.21); didn't
fix it.
> The timing may be a coincidence, though reading the post on
> trans() encourages me to make this post.  While I use 'trans' across
> functions, it is not applied on complex-valued matrices; only
> real-valued.  So the prior post wouldn't explain my issue.

Hi, I'm the main author of Armadillo.

I'm interested in hearing about all regressions -- can you provide
more details ?

There have been a lot of changes between Armadillo 1.2 and the latest
beta (1.99.3).  I'd like to shake out all known bugs before releasing


Dr Conrad Sanderson : Sr Research Scientist : NICTA :


This email message is for the sole use of the intended recipient(s) and
may contain confidential information. Any unauthorized review, use,
disclosure or distribution is prohibited. If you are not the intended
recipient, please contact the sender by reply email and destroy all copies
of the original message.

More information about the Rcpp-devel mailing list