From 6404d3da4501417ec72091ae8c42076e587312ab Mon Sep 17 00:00:00 2001
From: Johannes Pfeifer <jpfeifer@gmx,de>
Date: Thu, 18 Jul 2013 15:04:00 +0200
Subject: [PATCH] Provide additional debugging info before lnsrch1 crashes with
 error

---
 matlab/lnsrch1.m | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/matlab/lnsrch1.m b/matlab/lnsrch1.m
index ef63f44d5..80af34462 100644
--- a/matlab/lnsrch1.m
+++ b/matlab/lnsrch1.m
@@ -50,6 +50,24 @@ x = xold;
 nn = length(j2);
 summ = sqrt(sum(p.*p)) ;
 if ~isfinite(summ)
+    eq_number_string=[];
+    for ii=1:length(j1)-1
+        eq_number_string=[eq_number_string, num2str(j1(ii)), ', '];
+    end
+    eq_number_string=[eq_number_string, num2str(j1(end))];
+    var_string=[];
+    Model=evalin('base','M_');
+    for ii=1:length(j2)-1
+        var_string=[var_string, deblank(Model.endo_names(j2(ii),:)), ', '];
+    end
+    var_string=[var_string, deblank(Model.endo_names(j2(end),:))];
+    fprintf('\nAn infinite element was encountered when trying to solve equation(s) %s \n',eq_number_string) 
+    fprintf('with respect to the variable(s): %s.\n',var_string)
+    fprintf('The values of the endogenous variables when the problem was encountered were:\n')
+    for ii=1:length(xold)
+        fprintf('%-s % 8.4g \n',Model.endo_names(ii,:),xold(ii));
+    end
+    skipline();    
     error(['Some element of Newton direction isn''t finite. Jacobian maybe' ...
            ' singular or there is a problem with initial values'])
 end