Fig. 6From: Optimal principal component analysis of STEM XEDS spectrum imagesA suggested method to quantify the anisotropy of a scatterplot. The data points in the scatter plot are projected on the number of lines oriented under different angles \(\phi\). At each orientation, a histogram with a fixed number of s channels is calculated. Finally, the anisotropy criterion is calculated as in Eq. (11) by comparing all available projectionsBack to article page