H-2
Sample Program
vp_r - reference cell vapor pressure (kPa)
vp_s - sample cell vapor pressure (kPa)
kPa - total pressure (kPa)
*/
double Vref, gain, chi_ws, chi_wr, eff_cr, tc, eff_mv, result, inv_cal;
tc = temp_correction(Tirga);
if (Cr == 0.0) {
/* absolute mode
*/
chi_ws = chi(vp_s/kPa);
eff_mv = mV/chi_ws*p0_over_p(kPa);
result = chi_ws * cal(eff_mv) * tc;
return result;
}
/* differential mode
*/
chi_wr = chi(vp_r/kPa);
eff_cr = Cr / temp_correction(Tirga) / chi_wr;
inv_cal = inverse_cal(eff_cr);
Vref = chi_wr * inv_cal / p0_over_p(kPa);
gain = (1.0 - Vref/K_cal);
return ppm(Vref + mV*gain, 0, Tirga, 0, vp_s, kPa);
}
/* ------------------------------------------------------------------------- */
static double cal(double mv)
{
/* The basic irga cal equation - polynomial
*/
double rtn;
rtn = (A_cal + (B_cal + (C_cal + (D_cal + E_cal*mv)*mv)*mv)*mv)*mv;
return rtn;
}
/* ------------------------------------------------------------------------- */
