Representing NA values

[sdcoffey]

Representing NA values

[sdcoffey]

Hey @zhengyangfeng00, I like the idea! Definitely an omission from the library in it's current state. How would you feel about collaborating on this? If you send me a PR i'm happy to look at it, otherwise, i'll try to address this as soon as I have time

[zhengyangfeng00]

I'm happy to work on a PR. I'm experimenting with a very simple implementation:

package na

import (
	"math"
	
	"github.com/sdcoffey/big"
)

var (
	// NA is a decimal object that represents a result that cannot be calculated.
	NA = big.NewDecimal(float64(math.MaxInt64))
)

func IsNA(d big.Decimal) bool {
	return d.EQ(NA)
}

and it worked fine with my use cases. I basically have all indicators be aware of this NaN value. Essentially if an indicator depends on another one, then in its Calculate it first checks if the indicator it depends on calculates to NaN and if so, it returns NaN as well.

The majority of work I image is to update all existing indicators to behave similar?

[sdcoffey]

@zhengyangfeng00 Since this is more of a feature of big, i've moved this ticket here:
sdcoffey/big#3