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Comment by tedunangst | Hacker News Reader

Correct me if I'm wrong, but couldn't the same bug exist in the BigDecimal to double conversion? It has to turn a precise value into an approximate double using a similar algorithm, no?

    return base.scaleByPowerOfTen(exponent).doubleValue();

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I don't believe so; the conversion to imprecise doesn't follow the same logic that the String to double does. But I don't know what logic it does follow, nor if there's other bugs there :)

In any case, for the original value and variations I tested, the workaround does function properly.

My understanding is that you are correct. I believe that BigDecimal.doubleValue() does the conversion by (wait for it…) converting to a string and parsing with Double.parseDouble(). Real quick:

scala> val y y: java.math.BigDecimal = 2.2250738585072012E-308

scala> y.doubleValue() Hangs

This is one of those “harder than it looks” problems.

Yeah, I went back to my code and realized there was a precision problem I had to fix for numbers approaching 64-bit minimum. Once I fixed that issue, it went back to hanging again :(

I updated the post, and I'm looking for new alternatives now.

maybe its okay to lose some precision as everybody knows that doubles are already inaccurate? :)

http://en.wikipedia.org/wiki/Floating_point#Accuracy_problem...

edit: i mean: normalize(!), check if it is textually the bad magic number, then either use builtin conversion or use your solution. a? :)

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