Hi: On Fri, Jul 16, 2010 at 3:44 PM, skan <juanp...@gmail.com> wrote:
> > Hello > > I have a table of this kind: > > function x1 x2 x3 > 2.232 1 1 1.00 > 2.242 1 1 1.01 > 2.732 1 1 1.02 > 2.770 1 2 1.00 > 1.932 1 2 1.01 > 2.132 1 2 1.02 > 3.222 1.2 1 1 > ..... ... .. .. > > > The table represents the values of a function(x1, x2, x3) for each > combination x1, x2, x3. > > I'd like to generate a plot where each point has the coordinates x=x1, > y=x2, > z=(mean of function(x1, x2) for all different x3). How can I do it? > Here are three ways to get the function means over the x1 * x2 combinations - there are others, too. I changed the variable function to y since function is a basic object in R and therefore not a good choice of variable name. library(doBy) library(plyr) # (1) aggregate (s1 <- aggregate(y ~ x1 + x2, data = d, FUN = mean)) # (2) function summaryBy() in package doBy: (s2 <- summaryBy(y ~ x1 + x2, data = d, FUN = mean)) # (3) function ddply() in package plyr: (s3 <- ddply(d, .(x1, x2), summarise, y = mean(y))) All three give the same answer (apart from the name of the y mean): x1 x2 y 1 1.0 1 2.402 2 1.0 2 2.278 3 1.2 1 3.222 fox example, with the data from above the first point would be: > x=x1=1, y=x2=1, z=(2.232+2.242+2.732)/3 > > > In truth, my table has many columns and I want to take the mean over all > the > variables except the ones I represent at the axes, for example represent > function(x1, x2) taking the mean over x3, x4, x5. > Same as above. The response is averaged over all x1 * x2 combinations. > > Or using the maximum value of function(x1, x2) over all x1, x2, x3 > Substitute FUN = max for FUN = mean in aggregate() and summaryBy(), and use y = max(y) in place of y = mean(y) in the ddply() call. I presume you meant max f(x1, x2) over all x3 with the same (x1, x2) combination. > How can I do it? > > For the 3D plot, one choice is persp() in base graphics; another is cloud() in the lattice package. persp() requires setting up a rectangular grid of (x1, x2) pairs, with y = f(x1, x2) supplied as a n1 x n2 matrix. cloud() in lattice only requires a formula of the form y ~ x1 + x2. See their respective help pages for more details. The scatterplot3d package could also be used in this context. > Another question. > How can I plot function(x1, x2, x3) with x=x1, y=x2, z=x3, different > colours=function > One can create a vector of colors, but the question is too vaguely worded to give any specific advice. HTH, Dennis > > > > thanks > > > -- > View this message in context: > http://r.789695.n4.nabble.com/multivariate-graphs-averaging-on-some-vars-tp2292039p2292039.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
