  A program to compute photo-ionization functions and fitting parameters for an
efficient photo-ionization model is presented. The code integrates the product
of spectrum emission intensity, the photo-ionization yield and the absorption
coefficient to calculate the photo-ionization function of each gas and the
total photo-ionization function of the mixture. The coefficients of Helmholtz
photo-ionization model is obtained by fitting the total photo-ionization
function. A database consisting $\rm N_2$, $\rm O_2$, $\rm CO_2$ and $\rm H_2O$
molecules are included and can be modified by the users. The program provides
more accurate photo-ionization functions and source terms for plasma fluid
models.
