Error in re-building vignettes:
  ...
Loading required package: nlmrt
Error in nlsModel(formula, mf, start, wts) : 
  singular gradient matrix at initial parameter estimates
Error in nls(regmod, start = huetstart, trace = FALSE, data = pastured) : 
  singular gradient
Loading required package: optimx
Loading required package: numDeriv
Error in nlxb(eunsc, start = start1, lower = c(b1 = 0, b2 = 0, b3 = 0),  : 
  Infeasible start
Error in nls(eunsc, start = start1, lower = c(b1 = 0, b2 = 0, b3 = 0),  : 
  Convergence failure: initial par violates constraints
Error in nlxb(eunsc, start = start1, data = weeddata1, masked = c("b2",  : 
  All parameters are masked
Error in nlfb(start1, hobbs.res, hobbs.jac, lower = c(b1 = 0, b2 = 0,  : 
  Infeasible start
Error in nlfb(start1, hobbs.res, hobbs.jac, maskidx = c(3, 1, 2)) : 
  All parameters are masked
Loading required package: Rcgmin

Attaching package: ‘Rcgmin’

The following objects are masked from ‘package:optimx’:

    Rcgmin, Rcgminb, Rcgminu

Loading required package: Rvmmin

Attaching package: ‘Rvmmin’

The following objects are masked from ‘package:optimx’:

    Rvmmin, Rvmminb, Rvmminu

Warning in Rcgminu(par, fn, gr, control = control, ...) :
  A NULL gradient function is being replaced by numDeriv 'grad()'for Rcgmin
Warning in Rcgminb(par, fn, gr, lower = lower, upper = upper, bdmsk = bdmsk,  :
  x[3], set 1 to upper bound = 0.25
Warning in Rvmmin(start1, hobbs.f, hobbs.g, lower = c(b1 = 0, b2 = 0, b3 = 0),  :
  Parameter out of bounds has been moved to nearest bound
Warning in Rcgminb(par, fn, gr, lower = lower, upper = upper, bdmsk = bdmsk,  :
  x[3], set 1 to upper bound = 0.3
Warning in Rvmmin(start1, hobbs.f, hobbs.g, bdmsk = c(1, 0, 1), lower = c(0,  :
  Parameter out of bounds has been moved to nearest bound
Warning in Rcgminb(par, fn, gr, lower = lower, upper = upper, bdmsk = bdmsk,  :
  x[3], set 1 to upper bound = 0.3
Warning in Rvmmin(start1, hobbs.f, hobbs.g, bdmsk = c(1, 0, 1), lower = c(0,  :
  Parameter out of bounds has been moved to nearest bound
Loading required package: minpack.lm
Error: package or namespace load failed for ‘minpack.lm’ in dyn.load(file, DLLpath = DLLpath, ...):
 unable to load shared object ‘/home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/minpack.lm/libs/minpack.lm.so’:
  /home/hornik/tmp/R.check/r-devel-gcc/Work/build/Packages/minpack.lm/libs/minpack.lm.so: failed to map segment from shared object

Error: processing vignette ‘nlmrt-vignette.Rnw’ failed with diagnostics:
 chunk 25 (label = chunk17) 
Error in nls.lm(ones, lower = rep(-1000, 4), upper = rep(1000, 4), jres,  : 
  could not find function "nls.lm"
Execution halted