How to (not) use floating point numbers

[joepetrowski]

A lot of runtime developers ask about using floats in the runtime. Our knowledge base should include a page that:

1. Explains why floats are problematic, and
2. Tells people how to accomplish their goal without floats.

[JoshOrndorff]

See also JoshOrndorff/recipes#196

[coriolinus]

I suspect that most users who desire this feature can get what they need from substrate-fixed.

[joepetrowski]

I suspect that most users who desire this feature can get what they need from substrate-fixed.

Sure, but we still need a page explaining why floating point is not OK and listing some options and tools, of which substrate-fixed is certainly one.

[JoshOrndorff]

The acronym FP is a little ambiguous in this context.

[apopiak]

I'd like to take on this one.

[coriolinus]

@apopiak See JoshOrndorff/recipes#196

[apopiak]

Hey @joepetrowski , sorry but I've been dragging my feet on this one a little and now I'm neck deep in updating the weights for launch. I don't think I'll get to this in the next 1-2 weeks and it's been open for a while, so might be good to re-assign if it's a priority.
I talked to Marcio and he said he's willing to help (he's working on the implementation side of fixed point math in substrate).
I'd be happy to take this on again as soon as the substrate weights stuff is through.

[apopiak]

FYI #14 is a draft PR with the prep work for this.