/***************************************************************************
                 module classe zcent_hor_traadv_cen2.h  -  description
***************************************************************************/
// Mohamed Berrada
// locean-ipsl.upmc, Paris, October 20, 2009
//===========================================================================
//                          methode forward
forward (YREAL x1,YREAL x2,YREAL x3,YREAL x4,YREAL x5)
{ /*
	1	from	ua    	  		1  i	j    k    t-1
	2	from	va    	  		1  i	j    k    t-1
	3	from	ta    	  		1  i	j    k    t-1
	4	from	ta    	  		1  i	j+1  k    t-1
	5	from	ta    	  		1  i+1	j    k    t-1
  */
  double zfui,zfvj;
  if(Yt==TU)
    YS1=0.;
  else{
    if(Yi==NX-1 || Yj==NY-1 || Yk==NZ-1){
      YS1=0.;
    }
    else{
      zfui = 0.5*e2u(Yi,Yj)*x1;
      zfvj = 0.5*e1v(Yi,Yj)*x2;
      YS1 = zfui*(x3+x5);
      YS2 = zfvj*(x3+x4);
    }
  }
  //
}

//===========================================================================
//                         methode  backward

backward (YREAL x1,YREAL x2,YREAL x3,YREAL x4,YREAL x5)
{
  YJ1I1=0.;     YJ1I2=0.;     YJ1I3=0.;      YJ1I4=0.;      YJ1I5=0.; 
  YJ2I1=0.;     YJ2I2=0.;     YJ2I3=0.;      YJ2I4=0.;      YJ2I5=0.; 
  // if(Yt==6 && Yi==28 && Yj==3)  xtest("ua_1_dynspg_flt",YG1,Yi,Yj,Yk,Yt);
  if(Yt!=TU){  
    double zfui,zfvj, dzfui_x1=0.,dzfvj_x2=0.;
    if(Yi==NX-1 || Yj==NY-1 || Yk==NZ-1){
      YJ1I1=0.;     YJ1I2=0.;     YJ1I3=0.;      YJ1I4=0.;      YJ1I5=0.; 
      YJ2I1=0.;     YJ2I2=0.;     YJ2I3=0.;      YJ2I4=0.;      YJ2I5=0.; 
    }
    else{
      zfui     = 0.5*e2u(Yi,Yj)*x1;
      dzfui_x1 = 0.5*e2u(Yi,Yj);
      zfvj     = 0.5*e1v(Yi,Yj)*x2;
      dzfvj_x2 = 0.5*e1v(Yi,Yj);

      YJ1I1= dzfui_x1*(x3+x5);
      YJ1I2= 0.;
      YJ1I3= zfui;
      YJ1I4= 0.;
      YJ1I5= zfui;
      
      YJ2I1= 0.;
      YJ2I2= dzfvj_x2*(x3+x4);
      YJ2I3= zfvj;
      YJ2I4= zfvj;
      YJ2I5= 0.;
    }
  }
  //
  
  
}

  //===========================================================================
//*************************  FIN DU MODULE zcent_hor_traadv_cen2   *************************