Schematic diagram of the partition integral comparing method (PICM) for stellar CME detection. Panel A shows the Hα line profiles in a pre-processed file. Panels B and C show the maximum (∆S_max) and minimum values (∆S_min) of the ∆S_n, respectively. The ∆S_n is the absolute value of the difference between the integrals on the blue and red halves of each Hα profile. The vertical dotted black line represents the rest wavelength of the Hα line in each panel.