When working through chapter 9 problems, I found that the trim argument in the traceplot() command does not work as intended, leading to unintentionally hard to read plots.

See the section of code below

The issue is, if window does not exist, it sets

window <- c(trim,n_iter)
on line 265, but the wstart and wend, the variables that actually end up being used during plotting, have already been set on lines 252 and 253 and are never set again. Looking through the code history, it looks like the if( !missing(window)) and if( missing(window)) sections used to be in the opposite order, but were flipped and expanded for unrelated reasons, leading to the bug.

I will be submitting a pull request to set wstart and wend variables again below line 265 again, please accept if you find it to be appropriate.