Natural log for UDF
 

Hi,

My model is J= k1*ln(x1) and the below is my codes. However, i received parse error in the line in pink font, which i could not detect any syntax error. please help.

#include "udf.h"

#define FLUID_ID 1
#define k1 2.00e-4
#define x1 1.3847
DEFINE_PROFILE(flux, thread, np)
{
cell_t c;
real x[ND_ND];


begin_c_loop (c,thread)
{
/* centroid is defined to specify position dependent profiles*/
C_CENTROID(x,c,thread);
F_PROFILE(c,thread,np) =
k1*double log (double x1);

}
end_c_loop (c,thread)
}

I think the casting should be done with round paranthesis:

Thanks a lot. it works!