diff --git a/mex/sources/estimation/libmat/Vector.cc b/mex/sources/estimation/libmat/Vector.cc
index ad012c8a5725a430ae0e65a108523956a4c30b92..34d873a761736af2100cbdffde294434bcdae81e 100644
--- a/mex/sources/estimation/libmat/Vector.cc
+++ b/mex/sources/estimation/libmat/Vector.cc
@@ -29,6 +29,7 @@ Vector::Vector(size_t size_arg) : size(size_arg)
 
 Vector::Vector(const Vector &arg) : size(arg.size)
 {
+  data = new double[size];
   memcpy(data, arg.data, size*sizeof(double));
 }