UDF errors:
 

hi all , I've been trying to interpret my udf and I see these errors :

line 10: invalid type conversion: double -> pointer to double.

for this UDF :
#include "udf.h"
#include "mem.h"
DEFINE_GEOM(deforming,domain,dt,position)
{
cell_t c;
Thread *t;
real *position;
begin_c_loop_all(c,t)
{
position=1.6-0.368*exp(-0.1231*(C_P(c,t)/1000));
}
end_c_loop_all(c,t)
return;
}
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