[gzsakuraz]

Hi
I use face and cell loop and calculate the mass and area of the face and cell
I dont know why it show negative result according to printing on the console.

please help me

real A[ND_ND]; real area; real totalarea=0;

begin_f_loop(f,t){
t1 = THREAD_T0(t);
int ttt=THREAD_ID(t1);
c=F_C0(f, t);
if(ttt==40){
if(C_LIQF(c,t1)){
x=x+1;
if(C_UDMI(c,t1,0)<C_VOLUME(c,t1)*C_R(c,t1))
F_AREA(A,f,t);/*area vector on the surface*/
area = NV_MAG(A);
totalmass2=C_VOLUME(c,t1)*C_R(c,t1)+totalmass2;
real mass = evaporate*area*current_time; /*in kg*/
totalmass = mass + totalmass;
totalarea = area+totalarea;
C_UDMI(c,t1,1)=C_UDMI(c,t1,1)+mass; /*collect cumulative mass*/
F_UDMI(f,t,2)=1; /*collect the position where heat flux must be applied*/
/*make sure sum not exceed*/
z=z+1; /*check the numbers of cell*/

}
}
}