nonlin_ode: stop iterating on encountering a NaN

1 files changed, 2 insertions, 0 deletions

diff --git a/nonlin_ode.py b/nonlin_ode.py
index 1a145b9..b6d73d8 100644
--- a/nonlin_ode.py
+++ b/nonlin_ode.py
@@ -81,6 +81,8 @@ def nonlin_solve_1d(initial_guess, Fs, args, maxiter = 100, atol = 1e-14, grid =
         solution_new = _nonlin_solve_1d_iter(solution_old, grid, basis_vals, Fs, args)
 
         delta = np.max(np.abs(solution_new.coeffs - solution_old.coeffs))
+        if np.isnan(delta):
+            raise RuntimeError('nan')
         print delta
         if delta < atol:
             return solution_new