How to obtain a quantitative description of quadrilateral mesh quality?

[mo1shang]

Hi, thank you for your great work and open source spirit.
I've been using quadwild for a while now and I've found that quadwild can generate high quality quadrilateral meshes while maintaining the features.
I would like to ask how to obtain a quantitative description of the quadrilateral mesh quality. In your paper, you mention quantitative indicators such as angular deviation, aspect ratio, histogram of grid quality, and so on. While in the output of quadwild, I didn't see a description of the final quadrilateral mesh quality.
Looking forward to your reply.