Summarize a product
A ScaleProduct.
Ignored.
A "summary_ScaleProduct" object (the print method's argument).
A list of class "summary_ScaleProduct": name, desc, axes
(per-axis summary rows), total, coverage, joint_coverage,
joint_weights.
summary(scale_product(a = scale_example(), b = scale_example2()))
#> <summary of ScaleProduct>
#> axes: 2
#> a -> 'example' 4 frames, 7 atoms, key `unit`
#> b -> 'example2' 2 frames, 4 atoms, key `period`
#> atoms: 28