Math Formula: -1*0 = -0

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1

Dear all,

Just a little comment on Math Formula modul.

I have a Double column with some zeros and some other numbers in rows. I'm using Math formula to negate these numbers, like: -1*$myDoubleColumn$. On rows with zero the result is -0.

Finally i'm using (-1*$myDoubleColumn$)+1-1 which gives me the correct value, 0, but it tells me there is something internally wrong with Math Formula modul.

What do you think?

2

No, this is standard behaviour. Computers internally have two different  zeros (if working with floating point = real numbers), +0 and -0. This becomes important if you divide by zero because this can either be negative or positive infinity.