Include annotations

[fxchen]

Hey there Bob!

I've been a fan for years and recommended a few of your articles to friends.

When I read your article I found myself appreciating the detail you put into your notebook! I thought I'd share a small amendment I typically like to use with complex graphs to annotate training periods (to understand causation).

I added two sample annotations you had mentioned in your post (marathon training and bulking) so I thought I'd share back to your code base. Feel free to do with this what you'd like.

See the attachment for what this looks like on the figure

[btroia]

Thanks for the pull request! Yes, optional annotations would be a nice addition but I am leaning towards a slightly different way of implementing them to supplement the body comp data (to maintain a minimalistic look and feel)

1. Annotations should have start/end dates (if something happened on a single day, these values would be the same)
2. Below the primary chart/x-axis (or as a separate chart), display annotations in more of a Gantt style, i.e.:

I was planning on this type of chart to visualize the different measurement tools I have used over the years and their date ranges.

Another way (not as clean, IMO) is to add colored areas for each annotation: