From c82658a2a51ccbc02dfc658d99813950e76962e4 Mon Sep 17 00:00:00 2001
From: Johannes Pfeifer <jpfeifer@gmx,de>
Date: Sat, 1 Jun 2013 16:32:40 +0200
Subject: [PATCH] Bugfix for steady;

1.) Fixes cases where model was not truly linear, but Dynare did not catch mistake because fvec and jacob contained cancelling NaN
2.) Use correct error code 22 if NaN appear instead of generic 20
---
 matlab/evaluate_steady_state.m | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/matlab/evaluate_steady_state.m b/matlab/evaluate_steady_state.m
index 77d0c5897..b48a393f4 100644
--- a/matlab/evaluate_steady_state.m
+++ b/matlab/evaluate_steady_state.m
@@ -72,7 +72,16 @@ function [ys,params,info] = evaluate_steady_state(ys_init,M,options,oo,steadysta
             fh_static = str2func([M.fname '_static']);
             [fvec,jacob] = fh_static(ys_init,exo_ss, ...
                                      params);
-            if max(abs(fvec)) > 1e-12
+
+            ii = find(~isfinite(fvec));
+            if ~isempty(ii)
+                ys=fvec;
+                check=1;
+                disp(['STEADY:  numerical initial values or parameters incompatible with the following' ...
+                      ' equations'])
+                disp(ii')
+                disp('Check whether your model in truly linear')
+            elseif isempty(ii) && max(abs(fvec)) > 1e-12
                 ys = ys_init-jacob\fvec;
             else
                 ys = ys_init;
@@ -94,6 +103,9 @@ function [ys,params,info] = evaluate_steady_state(ys_init,M,options,oo,steadysta
             resid = evaluate_static_model(ys_init,exo_ss,params,M,options);
         end
         info(2) = resid'*resid ;
+        if isnan(info(2))
+            info(1)=22;
+        end
         return
     end