dynare

parameters  bet mu gamma delta alp phid omega z v zhf vhf mh mf gh gf
theta phil phik kappazh kappazf kappavh kappavf rhomh rhomf rhozh rhozf
rhovh rhovf rhogh rhogf r qh qf pf pa pb ya yb kh kf lh lf wh wf ih ivf ch cf ah
bh af bf;  

其中pf 需要用fsolve函数解出来

pf = fsolve(pfssfn,pf);

function f = pfssfn(pf)
   global M_
  bet = M_.params(1);
  mu = M_.params(2);
  gamma = M_.params(3);
  delta = M_.params(4);
  alp = M_.params(5);
  omega = M_.params(7);
  z = M_.params(8);
  v = M_.params(9);
  zhf = M_.params(10);
  vhf = M_.params(11);
  mh = M_.params(12);
  mf = M_.params(13);
  gh = M_.params(14);
  gf = M_.params(15);
  theta = M_.params(16);
  qh = M_.params(32);
  qf = M_.params(33);
  pf = 0.8;

  pa = ((1-omega-omega*pf^(1-theta))/(1-2*omega))^(1/(1-theta));

  pb = (((1-omega)*pf^(1-theta)-omega)/(1-2*omega))^(1/(1-theta));

  ya = (mu*(1-alp)*z*mh*(alp*pa/qh)^(alp/(1-alp))+(1-mu)*gh/pa) ...
           /(1-alp*mu-(1/v)*(1-mu)*(v^(1/(1-alp))*z-1+delta)*alp/qh);

  yb = (mu*(1-alp)*z*mf*((alp/qf)*(pb/pf))^(alp/(1-alp))+(1-mu)*pf*gf/pb) ...
           /(1-alp*mu-(1/v)*(1-mu)*(v^(1/(1-alp))*z-1+delta)*alp/qf);

  ah = (1-omega)*ya*pa^(1-theta);

  af = omega*yb*(pb/pf)*(pa/pf)^(-theta);

  f = ya - ah - af/(vhf^(alp/(1-alp))*zhf);

请问在dynare里是怎么调用外部函数的？？？