a compiled error fo UDF

Fluenter

Hi, everyone I am compiled a udf program. Namke comamnd showed a error message: "makefile<66>: fatal error U1023: syntax error in expression". But I cannot find the reason of error. Please someone help me.

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#include "udf.h" DEFINE_ON_DEMAND(viscosity_calc) { cell_t c,c0,c1; face_t f; Thread *t; Thread *f_thread; Thread *c_thread; Domain *d; real x[ND_ND]; int i;

thread_loop_c(c_thread,d) {

begin_c_loop(c,c_thread)

{

i=0;

c_face_loop(c,c_thread,i)

{

f = C_FACE(c,c_thread,i);

f_thread = C_FACE_THREAD(c,c_thread,i);

c0 = F_C0(f,f_thread);

c1 = F_C1(f,f_thread);

C_CENTROID(x,c,c_thread);

if (c1==NULL) printf("Boundray cell\n",x[0],x[1],x[2]);

}

}

end_c_loop(c,c_thread) } }

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