Best practices for plotting

[santisoler]

I noticed that some of the plots that are created on the Session 3 Notebook (the one that introduces matplotlib) lack of some elements like axes labels detailing what's being plotted, the units of the axes, etc.

I would suggest that every plot we make during the sessions might need to satisfy some basic requirements in order to encourage students to produce communicative plots from day one.
For example:

• always add axes labels expliciting what's being plotted.
• axes labels must also have units (if any).
• if more than one element is being showed on the same plot, add a legend.
• use a proper colormap
  • perceptually uniform colormaps are usually the best, unless diverging colormap is needed (Choosing Colormaps),
  • avoid using jet, rainbow or similar.
• keep plots accessible: watch for low contrast, small fonts, color blindness related issues, etc.
• titles are encouraged, but not mandatory.

Let me know what do you think and feel free to add any requirement that I might have missed!