Re: Comparing floating point values in Java


Eric Sosman wrote:
Philipp wrote:
[...]

I was calculating an array of float values from some user input. But
sometimes (rarely) the calculation cannot be done (this is correct
behavior).
I then want to mark these values by setting them to -1 and treat this
special case later on. So I later need to test for -1 in my array.

Perhaps you can avoid the entire issue by choosing a
different "distinguished value." Float.NaN, maybe, using
the Float.isNaN(float) method instead of an == test. (NaN
seems a more natural surrogate for "does not compute," too.)

--
Eric Sosman
esosman@xxxxxxxxxxxxxxxxxxx

Or even have a seperate boolean array to specify valid results.
Having a magic value isn't generally a good idea, although NaN would be
the way to go if you did.

.

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