>>> "Eric" == Eric S Fraga <esflists@gmail.com> writes:

   > On Thursday, 29 Nov 2018 at 12:38, Uwe Brauer wrote:
   >> Now org-babel-tangle works nicely, but when I try to export the org
   >> file to latex via org-export-dispatch

   > I think the default is
   > :exports results
   > so you what you want is either
   > :exports both
   > or
   > :exports code

Thanks, but I tried
#+begin_src matlab :tangle test.m  :export code   :wrap latex :padline no 
function [ll x]=mitest(A0,x0)
% initialization 
format long
epsi=1.e-3;
nit=0;
nmaxit=200;
Delta=10;
A=A0;
while Delta>epsi & nit<nmaxit
    nit=nit+1; % counter
#+end_src

The basic idea is.
That we do.
We also will

#+begin_src matlab  :tangle test.m :export both  :wrap latex :padline no 
    y=A*x0;
end
#+end_src


And I obtain always:
\begin{document}

%% [removed source block]
The basic idea is.
That we do.
We also will

%% [removed source block]
\end{document}