message: fewer iterations for example
diff: @@ -33,8 +33,8 @@ fn rosenbrock_hessian(x: &Array1<f64>) -> Array2<f64> {
  // hacky...
  let mut out = Array2::eye(2);
  out[(0, 0)] = bla[0];
  - out[(0, 1)] = bla[1];
  - out[(1, 0)] = bla[2];
  + out[(0, 1)] = bla[2];
  + out[(1, 0)] = bla[1];
  out[(1, 1)] = bla[3];
  out
  }
  @@ -56,7 +56,7 @@ fn run() -> Result<(), Error> {
  let init_param: Array1<f64> = Array1::from_vec(vec![1.2, 1.2]);
  // let init_param: Vec<f64> = vec![-1.2, 1.0];
  - let iters = 1000;
  + let iters = 10;
  let mut solver = TrustRegion::new(Box::new(cost), init_param);
  solver.set_max_iters(iters);
  solver.add_logger(ArgminSlogLogger::term_noblock());
  