Implement average() for more numeric types

[knothed]

Currently, func average() -> Double is defined as an extension on Collection where Element == Double. What about CGFloats?

I suggest to add a protocol Field (based on algebraic fields) providing addition, multiplication and division with Self elements, and also a zero and one element. This would allow both average() and sum() to be implemented more generically. Double, Float and CGFloat could conform to this protocol (with nearly no additional implementation effort).

The integer case would have to be treated specially though.

[Jeehut]

CGFloats are Doubles. It's just a typealias. Just command-click it and you'll be amazed. ;)

Please note that there are many libraries providing such mathematical extensions to Swift. HandySwift is only targeting to add the most common things that we think should be part of Swift in the first place. I don't think we should dive too much into such things and recommend other tools that are already amazing at such things instead.

If you really wanted to add such things, please consider searching through the Swift Forums for existing suggestions or pitching your idea there and discussing a bit before making a bigger pull request here. For now, I consider this a non-bug. I'll reopen if necessary.

[knothed]

I'm not quite sure what you mean by CGFloats are Doubles. I know that they are the same, at least on 64-bit systems, but that still doesn't allow me to provide a CGFloat as an argument to a function that has a Double as its parameter.

As a consequence, I cannot calculate the average of 2 CGFloat-values without first converting them to Double and then converting the result back to a CGFloat, resulting in code like this:

let averageXY = CGFloat([Double(view.frame.origin.x), Double(view.frame.origin.y)].average())

Also, I think you quite misunderstood my intent – I just wanted to generalize the sum and average methods to CGFloats and Floats. I do not want to provide any kind of mathematical extensions or further, more complex, mathematical stuff. :)

The natural consequence of generalising average calculation is a protocol providing the required basic arithmetic operations: addition and division. The implementation would be extremely minimal because all targeted Swift types already provide these functions.

[Jeehut]

Ah yeah, sorry, I mixed things up with TimeInterval. Of course CGFloat is its own type. 😅

Okay, I'll reopen this. Could you please just post a PR with the approach you mean? I think then the discussion about the details of the implementation will be much easier. Currently, I'm not entirely sure what your suggested approach is. A PR would make that very clear. :)

[knothed]

Yes, I'll drop a PR. Thank you very much for reconsidering :)