Histogram of the obtained gradient slopes in the fits for both 12+log(O/H) and log(N/O) for different categories attending to the number of obtained breaks. Slopes for 12+log(O/H): a) galaxies with no breaks, b) galaxies with one single break, and c) galaxies with two breaks. The lower plots d), e), and f) are similar to the above ones but are for the log(N/O) radial gradient. For all plots, solid black lines represent the flattened profile (∇ = 0).