[vast01]

at first my code:

#include "udf.h"

DEFINE_SPECIFIC_HEAT(specific_heat_N2, T, Tref, h, yi)
{
real cp;
real temp = T;
real A0 = 1.0787e3;
real A1 = 3.059e-1;
real A2 = 6.6177e-4;
real A3 = 2.6368e-7;
real A4 = 2.1333e-12;
real A5 = 1.886e-3;
real A6 = 273;
real Y0;
real pressure;
pressure = C_P(c,t);

Y0 = A0-A1*temp+A2*(pow(temp,2))-A3*(pow(temp,3))- A4*(pow(temp,4)) ;
cp = Y0 *(1+A5*((pressure/10e5)-1)*(pow((A6/temp),2.4))); //[J / kg K]
*h = cp;

return cp;
}

The problem is that the index variable c and the thread pointer t are not passed to the UDF, but they are needed in the cell-pressure marco.
What do I have to do?