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Welcome to the Posit wiki!

I was just wondering where to put all my raves and ideas on Posit and associated stuff, and obviously, the Wiki is the place !

I only discovered Posits recently (end of July), and I found this a quite exciting idea, since the Arduino (8-bit AVR, not the various 32-bit architectures) is not particularly efficient when handling 4-byte floats.

Genesis of the interest

In my original home project (not on GitHub), started in 2013, I used panstamps (image) to manage a domestic floor heating system combining a heat pump and solar panels. One of the issues was the limited precision and variability of the ATmega328p ADC used for the temperature sensors (NI1000 resistors with long cables). Another issue was the hour-long delay between starting or stopping the floor heating and the impact on ambient temperature, which was additionally impacted by natural solar radiation through the windows. So I tried several filtering and extrapolation strategies using fixed-point arithmetic. I may make those into a public Arduino library on GitHub as well ... some day.

Today, I intend to move to reinforcement learning, since the filtering and extrapolation never delivered an optimum strategy for comfort and consumption. On top of that, auto-consumption of photovoltaic-generated electricity will be required in a few years. Posit numbers may be a solution to avoid using too much memory.

Some links on Posits

• Anatomy of a posit number and Comparing range and precision of IEEE and posit, John D. Cook's blog, 11-14/04/2018
• Posits: the good, the bad and the ugly., Florent de Dinechin et al., 2019
• Visualisation of small Posit sizes on a circle