R Under development (unstable) (2023-11-25 r85635 ucrt) -- "Unsuffered Consequences"
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> 
> library(nleqslv)
> 
> # Dennis Schnabel example 6.5.1 page 149
> f <- function(x) {
+     y <- numeric(2)
+     y[1] <- x[1]^2 + x[2]^2 - 2
+     y[2] <- exp(x[1]-1) + x[2]^3 - 2
+     y
+ }
> 
> # check error handling in control argument
> try(nleqslv(f,control=list(1e-3)))
Error in nleqslv(f, control = list(0.001)) : 
  'control' argument must be a named list
> try(nleqslv(f,control=list(f=1e-3)))
Error in nleqslv(f, control = list(f = 0.001)) : 
  unknown names in control: 'f'
> try(nleqslv(f,control=list(f=1e-7,b=1e-3)))
Error in nleqslv(f, control = list(f = 1e-07, b = 0.001)) : 
  unknown names in control: 'f', 'b'
> 
> proc.time()
   user  system elapsed 
   0.10    0.04    0.15