Formula doesn't give same results when surrounded by brackets

**EMaster** · 12-16-2013, 10:18 PM

I have a formula that is simply the following:

Formula:

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The result of the formula = 0

However, if I then change that formula to surround it with brackets, so it is like this:

Formula:

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The answer ends up being 0.0000000000582076609134674

I get the same behaviour if that formula is nested in another formula, for example:

Formula:

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Why does adding brackets around the formula creating a (slightly) different result?

**protonLeah** · 12-16-2013, 10:57 PM

What are you trying to do with SUM(B1,Z1)? Are you just adding two cells, B1 + Z1, or are you trying to add the whole range from B1 through Z1?

**EMaster** · 12-16-2013, 11:00 PM

My apogies, i meant to write:

Formula:

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i.e. summing A1 through to Z1

**MrShorty** · 12-17-2013, 12:06 AM

I can never find these knowledge base articles from Microsoft, but this is an artifact of the way Excel implements the IEEE double precision floating point arithmetic. Basically, because of the inherent limitations in computer arithmetic, sometimes A-A does not come out to exactly 0. Excel's programmers have tried to account for this, so sometimes they artificially force 0, but it is not always there. In the long run, we as programmers need to be able to accept that computer arithmetic has a built in error, and need to try to minimize that error and otherwise deal with it.

Try this article: http://support.microsoft.com/kb/78113