Re: [R] operations on a list

From: <szhan_at_uoguelph.ca>
Date: Sat 10 Dec 2005 - 05:30:15 EST

Hello, Jacques,
Thank you very much for your help!
It's clever code and works fine. But I don't understand what the last line code is for. Should I really need the last line? Thanks again.
Josh

Quoting Jacques VESLOT <jacques.veslot@cirad.fr>:

> you could try :
>
> trt1 <- do.call("rbind", lapply(listexp, function(x) {
> zz <- aggregate(t(x), list(rep(1:3, each=2)), mean)[,-1]
> zz <- as.matrix(zz)
> sweep(zz[1:2,], 2, zz[3,], "-")[1,]}))
>
> trt2 <- do.call("rbind", lapply(listexp, function(x) {
> zz <- aggregate(t(x), list(rep(1:3, each=2)), mean)[,-1]
> zz <- as.matrix(zz)
> sweep(zz[1:2,], 2, zz[3,], "-")[2,]}))
>
> expeffect <- list(trt1=trt1, trt2=trt2)
>
> expeffect <- lapply(expeffect, function(x) {names(x) <- names(listexp) ; x})
>
>
>
>
> szhan@uoguelph.ca a écrit :
>
> >Hello, Everyone,
> >I am sorry that my message got truncated due to wrong format.
> >I hope it works now:
> >
> >Hello, R Users,
> >I have a list (say listexp) of 10,000 elements, each of which consists of a
> >matrix (5X6). It likes:
> >$"a"
> > trt1rep1 trt1rep2 trt2rep1 trt2rep2 ctlrep1 ctlrep2
> >[1,] 50 54 98 89 40 45
> >[2,] 60 65 76 79 34 43
> >[3,] 86 83 34 45 38 34
> >[4,] 67 78 88 98 45 41
> >[5,] 55 59 77 88 56 66
> >$"b"
> > trt1rep1 trt1rep2 trt2rep1 trt2rep2 ctlrep1 ctlrep2
> >[1,] 55 54 88 86 42 40
> >[2,] 66 65 86 99 44 48
> >[3,] 80 86 44 55 38 44
> >[4,] 77 78 98 92 35 41
> >[5,] 50 53 87 88 46 56
> >
> >.
> >
> >I want to perform some operations on the list and then got a new list(say
> >expeffect) like this:
> >1. first average two replicates for each row in the matrix shown above (like
> for
> >treatment 1 using (trt1rep1+trt1rep2)/2) and get one value for each
> >treatment/control
> >2. then subtract average value of the control from the each treatment and
> get
> >one value for the treatment effect for each row in the matrix shown above
> >3. make a new list (say trteffect) with 2 elements (trt1 and trt2), each of
> >which consists of a matrix (10,000X5)with a row name same with old list's
> >element name, a column name corresponding to the row name of old list's
> matrix
> >like:
> >$"trt1"
> > [,1] [,2] [,3] [,4] [,5]
> >a 9.5 24 48.5 29.5 -4
> >b 13.5 19.5 42 39.5 0.5
> >.
> >
> >$"trt2"
> > [,1] [,2] [,3] [,4] [,5]
> >a 51 39 3.5 50 21.5
> >b 46 46.5 8.5 57 30.5
> >.
> >
> >Could you please help me to make this new list (expeffect)?
> >Thank you in advance!
> >Joshua
> >
> >______________________________________________
> >R-help@stat.math.ethz.ch mailing list
> >https://stat.ethz.ch/mailman/listinfo/r-help
> >PLEASE do read the posting guide!
> http://www.R-project.org/posting-guide.html
> >
> >
> >
>
>
>



R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html Received on Sat Dec 10 05:43:16 2005

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