# In the siunitx package, how do i get it to produce uncertainties with the \pm symbol instead of parenthesis

Using the siunitx package, if I specify an error with the \pm symbol then it automatically converts it to a form using parenthesis. I would like it to not do this and keep the \pm symbol, but still space the elements of the quantity and symbol in a good way.

e.g. \SI{10 \pm 2}{\kelvin} would produce 10(1) k

I would like it to produce: 10\pm1 k or something similar with spacing taken care of.

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You want the separate-uncertainty switch, p.30 of the documentation.

\usepackage[separate-uncertainty=true]{siunitx}


sets this format for every number, or

\SI[separate-uncertainty=true]{whatever}


just for one.

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Ant, you're a star, just the correct option. I'm surprised I didn't find it myself as I thought I did a search for "uncertainty" in the manual. No matter. Thanks very much –  aghsmith Sep 6 '11 at 21:45

I've just come across the same problem and this is how I solved it to my satisfaction:

in the preamble:

\usepackage[separate-uncertainty = true,multi-part-units=single]{siunitx}


in the text:

(\SI{284(10)}{\ampere})


Produces the following output: 284 ± 10 A

If multi-part-units=single option isn't given, the result will look like: ((284 ± 10) A) which, in my opinion, is less than optimal.

HTH

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