Simplify RxODE syntax

[mattfidler]

Hi Andy,

I just submitted a pull request to simplify the RxODE syntax in your vignette. The new syntax is:

ff_ode_rx <- function(model_switch, xt, p, poped.db){
  times_xt <- drop(xt)
  et(0,amt=p[["DOSE"]], ii=p[["TAU"]], until=max(times_xt)) %>%
    et(times_xt) -> data
  
  out <- rxSolve(modrx, p, data, atol=1e-8, rtol=1e-8,maxsteps=5000,
                 returnType="data.frame")
  
  y <-  out$CP[match(times_xt,out$time)]
  
  return(list(y=matrix(y,ncol=1),poped.db=poped.db))
  
}

It skips some marginal post-processing and pre-processing and data accessing within R.

In addition I rebuilt the pkgdown website

[andrewhooker]

Great, thanks for the update! Should there be a speed up in computations as well?

[mattfidler]

No speed up in computation based on current CRAN RxODE, but speedup will be coming in the next release;