//exec('fstyp12.2.ex')
    hd=ones(1,32);hd(65)=0;//definition of samples
    hst1=fsfirlin(hd,1);//type 1 filter
    hst2=fsfirlin(hd,2);//type 2 filter
    pas=1/prod(size(hst1))*.5;
    fg=0:pas:.5;//normalized frequencies grid
    plot(fg,hst1);
    dess(54:55)=[1;2];
    plot(fg,hst2);
