diff --git a/matlab/set_prior.m b/matlab/set_prior.m
index 1bef12aff..e63780864 100644
--- a/matlab/set_prior.m
+++ b/matlab/set_prior.m
@@ -259,6 +259,7 @@ if options_.initialize_estimated_parameters_with_the_prior_mode
     if ~isempty(k)
         xparam1(k) = bayestopt_.p1(k);
     end
+    xparam1 = transpose(xparam1);
 end 
 
 % I create subfolder M_.dname/prior if needed.