Hello,

New Eigen user here. On top of that, not a programmer by trade, but a physicist, so I might ask really basic questions. I apologize in advance.

I have been reading on the library to see if it will fit our needs. So far, it does. I have only one question about the statistical capabilities of Eigen. I have easily found the mean function, but would have liked to get a standard deviation (variance would be OK ) function. I have written one, but was wondering if there is one already in Eigen that I have missed. Browsed the source code (i.e. grep) and the internet (i.e. Google) for it, but did not find it.

I have found this information on the Eigen site:
http://eigen.tuxfamily.org/index.php?title=Todo
which points to a dead link on Bitbucket about a statistics module for Eigen. Is it dead ? If not, what is the correct link ? If it is dead, why ? Any plans to revive it ? Really not a group of professional programers, but can we help ?

Anyhow, thanks for any info on that.

Ghyslain

Indeed, this fork seems to be dead. Currently I'm not aware of anybody working on such a Statistic module, but anyone is welcome to jump in and resurrect it. It's an opensource project developed with an opensource spirit

Hi.

Thanks for the quick answer.

I am looking into the extension mechanism of Eigen with the preprocessor macros. Not certain, but this might be sufficient for us.

I have nonetheless cloned the Mercurial repository and I am also looking at the possibility of submitting my work, but I think some of the mechanism are over my head and the quality of my proposed patches won't be on par with the rest of the library. I believe the variance could be a new redux, if I understand the design properly, but from the discussion thread that the To Do pointed to, it does not seem to be the preferred direction...

Anyhow, again, thanks for the answer.

yes, the plugin mechanism or a free function should be enough to simply add a variance/stdvar method.