Read the documentation.
If you make use of this code, please cite the JOSS paper:
@article{corner,
Author = {Daniel Foreman-Mackey},
Doi = {10.21105/joss.00024},
Title = {corner.py: Scatterplot matrices in Python},
Journal = {The Journal of Open Source Software},
Year = 2016,
Volume = 24,
Url = {http://dx.doi.org/10.5281/zenodo.45906}
}