chisq¶

gdt.core.spectra.fitting.chisq(obs_counts, back_rates, back_var, mod_rates, exposure)[source]¶

Chi-Square Likelihood

Parameters:

obs_counts (np.array) – The total observed counts
back_rates (np.array) – The background model count rates
back_var (np.array) – The background model count rate variance
mod_rates (np.array) – The model source rates
exposure (float) – The source exposure

Returns:

(float)