Running examples in ‘xxIRT-Ex.R’ failed
The error most likely occurred in:

> ### Name: mst
> ### Title: Multistage Testing
> ### Aliases: mst mst.assemble mst.assemble.sequence mst.constraint mst.get
> ###   mst.objective mst.route mst.sim mst.stagelength mst.summary plot.mst
> ###   print.mst
> 
> ### ** Examples
> 
> # generate an item pool
> pool <- gen.irt(1, 200)$items
> pool$content <- sample(1:3, nrow(pool), replace=TRUE)
> # 1-2-3 design with 2 parallel panels
> x <- mst(pool, c(1, 2, 3), 2)
> # remove route with radical changes from the 1-3-3 design
> x <- mst.route(x, c(1, 2, 6), "-", print=TRUE)
  stage1 stage2 stage3
1      1      2      4
2      1      3      4
3      1      2      5
4      1      3      5
6      1      3      6
> x <- mst.route(x, c(1, 3, 4), "-", print=TRUE)
  stage1 stage2 stage3
1      1      2      4
3      1      2      5
4      1      3      5
6      1      3      6
> # maximize information at -1.0/0/1.0 for low-/mid-/high-ability routes
> x <- mst.objective(x, -1.0, Inf, routes=1)
> x <- mst.objective(x,  0.0, Inf, routes=2:3)
> x <- mst.objective(x,  1.0, Inf, routes=4)
> # all routes to have 10 items
> x <- mst.constraint(x, "len", NA, 10, 10)
> x <- mst.constraint(x, "content", 1, 3, 3)
> # all least 2 items each stage
> x <- mst.stagelength(x, 1, 2, 10)
> x <- mst.stagelength(x, 2, 2, 10)
> x <- mst.stagelength(x, 3, 2, 10)
> # assemble
> x <- mst.assemble(x)
No solution.> # check content
> for(p in 1:x$npanel){
+  for(r in 1:x$nroute){
+    cat("Panel #", p, " Route #", r, ", Content Area 1 has ",
+    freq(mst.get(x, panel=p, route=r)$content, 1:3)$n[1], " items.\n", sep="")
+  }
+ }
Panel #1 Route #1, Content Area 1 has 0 items.
Panel #1 Route #2, Content Area 1 has 0 items.
Panel #1 Route #3, Content Area 1 has 0 items.
Panel #1 Route #4, Content Area 1 has 0 items.
Panel #2 Route #1, Content Area 1 has 0 items.
Panel #2 Route #2, Content Area 1 has 0 items.
Panel #2 Route #3, Content Area 1 has 0 items.
Panel #2 Route #4, Content Area 1 has 0 items.
> # check TIFs
> plot(x, by.route=TRUE)
Error in mst.summary(x, ...) : items haven't been assembled yet.
Calls: plot -> plot.mst -> mst.summary
Execution halted