function F=pdeasmf(it1,it2,it3,np,ar,x,y,sd,u,ux,uy,time,f)
%PDEASMF Assemble the f coefficient.

%       A. Nordmark 12-19-94.
%       Copyright (c) 1994-98 by The MathWorks, Inc.
%       $Revision: 1.8 $  $Date: 2000/09/02 04:23:39 $

f=pdetexpd(x,y,sd,u,ux,uy,time,f);
f=f.*ar/3;
F=sparse(it1,1,f,np,1);
F=F+sparse(it2,1,f,np,1);
F=F+sparse(it3,1,f,np,1);

