[R] Plot multiple columns

[Ben Bolker]

Noah Silverman <noah <at> smartmediacorp.com> writes:

> 
> I'm running a long MCMC chain that is generating samples for 22 variables.
> 
> I have each run of the chain as a row in a matrix.

> So:  Chain[,1] is the column with all the samples for variable one. 
> Chain[,2] is the column with all the samples for variable 2, etc. 

  The previous 2 paragraphs seemed contradictory until I realized
that in the first paragraph you are using "run" to mean what I would
usually call a "sample" ...

> I'd like to fit all 22 on a single page to print a nice summary.  It is
> OK if the graphs are small, I just need to show the overall shape and
> convergence.

  How about for example

> x <- matrix(runif(22000),ncol=22)
> library(coda)
> m <- as.mcmc(x)
> xyplot(m)
> xyplot(m,layout=c(4,6))