Wow, this is great! also easily customizable I played around with it and made some modifications to fit my project better, first I made 12 bars instead of 15 for convenient storage in the array where I have all the month's information so I can associate every bar with a month and just save the data.height with their corresponding month to use the formula. It makes the curve less accurate but It's not a big deal.
But since I was fascinated by the graph I played around while trying to understand the maths ended up adding tracking for the days displaying all the information for each day as the dot moves at increments of graphwidth/365 days.
The dot moves to 365 positions representing the days of the year, I don't know why but there's sometimes a weird 0,01 window of error on the temperature value from using the keyboard or the play bottom vs using the mouse.
Anyway, thanks Rojo awesome tricks Learnt a lot!