add sleep credit statistics
from an e-mail from Richard B. <...>:
Hi There, I downloaded your app and had a thought. i was taught that you could never have more than 8 hours sleep credit, ie if you slept for 2 days you would still only have 8 hours sleep credit.is there a way of putting in a limit in your calculations in your program?
PS excellent app
He later told me that the cap only applies to positive balance and doesn't affect debt. He says this came from flight training course on human performance.
Later he said this:
When I was taught about sleep I was given a few basic bits rules.
- 1 hour sleep = 2 hours credit, i.e. 2 hours of awake time. So after 8 hours sleep you get 16 credits.
- You can earn a maximum of 16 credits.
- If you stay awake more hours than you have credits then you can go into –ve credit, in other words debt. Sleep will first go into repaying the debt before giving you credit.