BPT diagram obtained by the ANN_R trained with the CALMa set. Arrows point in the direction towards the location where galaxies should be placed according to their position in the SDSS MPA-JHU DR8 catalog. The color represents the distance for each point between the two BPT diagrams. The solid (ka03), dashed (Ke01) and dotted lines (S07) define the regions for the four main ionization mechanisms of galaxies. The percentage for each group is shown in black. The histograms on the rights represent the angular distribution of the arrows for Star forming, Seyfert and composite galaxies. The angle is defined as a clockwise rotation towards the x axis.