plot_pca_variance.RdPlot the variance explained by each PCA component. The number of
components shown is controlled by num_components, with up to the
first 10 componenets shown by default. If less than the requested number of
components exist, then all the components will be shown.
plot_pca_variance(pca, num_components = 10)output of pca_wsaf() function.
maximum components to be shown.