From fd09ba1fca3e5e152a06cd0d9a6a2432c3bd857b Mon Sep 17 00:00:00 2001
From: Houtan Bastani <houtan@dynare.org>
Date: Tue, 5 Feb 2019 16:38:25 +0100
Subject: [PATCH] ols_style parsing: remove regressors that are equal to zero

---
 matlab/ols/parse_ols_style_equation.m | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/matlab/ols/parse_ols_style_equation.m b/matlab/ols/parse_ols_style_equation.m
index cd93e4de2..7a2289ac3 100644
--- a/matlab/ols/parse_ols_style_equation.m
+++ b/matlab/ols/parse_ols_style_equation.m
@@ -179,6 +179,12 @@ end
 Y = Y(fp:lp);
 if ~isempty(X)
     X = X(fp:lp);
+    names = X.name;
+    for i = 1:length(names)
+        if all(X.(names{i}).data == 0)
+            X = X.remove(names{i});
+        end
+    end
 end
 if ~isempty(lhssub)
     lhssub = lhssub(fp:lp);