Post-processing fails when only 1 parameter is monitored

[mikemeredith]

I have hit a problem when I have only 1 parameter I want to monitor. JAGS runs ok, then I get

Calculating statistics....... 
Error in strsplit(params, "\\[") : non-character argument

I hit this first with jagsUI 1.3.7, but same problem with 1.3.9. Here's an example:

library(jagsUI)

modelstring = "
model {
    # Prior:
    tau <- pow(40, -2)    # Calculate precision for SD=40
    N ~ dnorm(448, tau)   # No. of ou in whole area
    n <- N * a            # No. of ou in area a
    # Likelihood:
    C ~ dpois(n)
} " # close quote for modelstring
writeLines(modelstring, con="model.txt")

jagsData <- list(a = 1/8, C = 45)

jagsout <- jags(jagsData, inits=NULL, parameters.to.save="N",  model.file="model.txt",
     n.chains=3, n.adapt=100, n.iter=1100, n.burnin=100, n.thin=1, DIC=FALSE)

It doesn't happen if DIC=TRUE, as then deviance is also monitored, nor when I insert a dummy parameter in the JAGS model (dummy ~ dnorm(0, 1)) and monitor that as well.

Could this be due to R's habit of changing 1-column matrices to vectors? If so, may need a [..., drop=FALSE] somewhere.

---

sessionInfo()
R version 3.2.3 (2015-12-10)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 7 x64 (build 7601) Service Pack 1

locale:
[1] LC_COLLATE=English_United Kingdom.1252 
[2] LC_CTYPE=English_United Kingdom.1252   
[3] LC_MONETARY=English_United Kingdom.1252
[4] LC_NUMERIC=C                           
[5] LC_TIME=English_United Kingdom.1252    

attached base packages:
[1] stats     graphics  grDevices utils     datasets  methods   base     

other attached packages:
[1] jagsUI_1.3.9    lattice_0.20-33

loaded via a namespace (and not attached):
[1] parallel_3.2.3 coda_0.18-1    grid_3.2.3     rjags_4-4     

[kenkellner]

Mike,

I uploaded a new package version (1.4.0) that should fix this problem. Thanks as always for your input.

[mikemeredith]

Thanks Ken! Works fine now.