Column(row)wise minimum and maximum
This is why the matrixStats package was created, cf. http://cran.r-project.org/web/packages/matrixStats/ 1. Yes, it would be nice to have them in one of the default packages. 2. We decided to focus on/constrain ourselves matrices in matrixStats. We decided not to go into arrays with length(dim(.)) >= 3. /Henrik
On Thu, Apr 19, 2012 at 11:39 AM, Ravi Varadhan <rvaradhan at jhmi.edu> wrote:
Oliver, It is mainly a speed issue (and also compactness!), at least for me. ?Using `apply' is so much slower. ? I agree with you that having column and row operations available for "basic" stats operations in "base" would be great. David - I am aware of capabilities in other packages, but I am hoping that such basic operations would be part of "base" distribution. Ravi -----Original Message----- From: oliver [mailto:oliver at first.in-berlin.de] Sent: Thursday, April 19, 2012 2:34 PM To: Ravi Varadhan Cc: r-devel at r-project.org Subject: Re: [Rd] Column(row)wise minimum and maximum On Thu, Apr 19, 2012 at 08:31:56PM +0200, oliver wrote:
On Thu, Apr 19, 2012 at 06:12:30PM +0000, Ravi Varadhan wrote:
Hi, Currently, the "base" has colSums, colMeans. ?It seems that it would be useful to extend this to also include colMin, colMax (of course, rowMin and rowMax, as well) in order to facilitate faster computations for large vectors (compared to using apply). ?Has this been considered before? ?Please forgive me if this has already been discussed before.
[...] Not sure if the performance of apply is so much of a problem, but also from a view of consistency of the provided functions, I think offering such functions would make it more clear and consitent to use R here, because all those functions are then available for row and col and the functionality is appended in the name (Mean, Sum etc.). I think the basic things that should be available woud be: ?- mean ?- median ?- min ?- max ?- var ?- sd
? - sum ? :-) ? - diff Ciao, ? Oliver
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