From villegas.ro at gmail.com  Tue May  8 21:05:58 2007
From: villegas.ro at gmail.com (R. Villegas)
Date: Tue, 8 May 2007 21:05:58 +0200
Subject: [Rd] Median
In-Reply-To: <4640AE97.4040007@integromics.com>
References: <4640AE97.4040007@integromics.com>
Message-ID: <29cf68350705081205g39b5fa21y5f62f9cde3e442b1@mail.gmail.com>

2007/5/8, Jose Sierra <jose.sierra at integromics.com>:
> Hello.
>
> I need calculate the median of several column of a data.frame, in a new
> column of this data frame, but the median operator only calculate from a
> vector.
>
> I have made a functionc that calculate the median but it is very slow.
> Are there any method in any package to calculate this?
>
> Best regards.
> Jose Sierra.
>
>            A                        B                        C
> -0.01678042      -0.0003354948     -0.0003354948
>  0.17320485       0.2359448911      0.4884204711
> -0.76066019      -0.6024409891     -0.5814788340
> -0.04365426      -0.0060560612     -0.0025470274
>  0.01885735       0.0027792718      0.0184081858
> -0.07275884      -0.0371542622     -0.0315041630
>   0.05740122       0.0814235514      0.0468193512
>  -0.05404834      -0.0590145580      0.0489612929
>  -0.28197518      -0.1899247807     -0.2089076920
>  -0.02465713      -0.2222512947     -0.2688619668
>
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

Maybe you can start with this:

m2 <- data.frame(matrix(c(
-0.01678042,      -0.0003354948,     -0.0003354948,
 0.17320485,       0.2359448911,      0.4884204711,
-0.76066019,      -0.6024409891,     -0.5814788340,
-0.04365426,      -0.0060560612,     -0.0025470274,
 0.01885735,       0.0027792718,      0.0184081858,
-0.07275884,      -0.0371542622,     -0.0315041630,
 0.05740122,       0.0814235514,      0.0468193512,
-0.05404834,      -0.0590145580,      0.0489612929,
-0.28197518,      -0.1899247807,     -0.2089076920,
-0.02465713,      -0.2222512947,     -0.2688619668
),nrow=10))

m2[,4]<- median(m2[,1])
m2[,5]<- median(m2[,2])
m2[,6]<- median(m2[,3])

Rod.



[Rd] Median
R. Villegas