Morning all… I think that there are several issues in the interplay of the \units and \digits command that could be a bit better (Sorry Hans…all meant in the best possible way). So here is a complete example and the pdf I get, after some experimentation. With kludges of my own. I'd guess there are several people using ConTEXt for the sciences, so this may help some, or some may set me on a better path… ___ \starttext \setdigitmode 6 {\em digit exponent powers - don't work} \digits{20e-12} \digits{-123.222,00e-12} % this one gives nothing at all But it seems it should \emdash\ ConTEXt magazine3 May 2003, from which the following non-working examples come \digits 123.222,00^10 % this one gives nothing at all \digits 123.222,00e10 % this one gives nothing at all \digits /123.222,00e-12 % this one gives nothing at all \digits -123.222,00e-12 % this one gives nothing at all \digits +123.222,00e-12 % this one gives nothing at all {\em spacing and decimal points} \digits 12,345,000.90 Has the same effect as this hard-coded beasty. 12~345~000.78 Digits without exponents seem to work.... \digits 1230.92 \digits{12,460,800.89} {\em Now a little challenge - write out the speed of light, with units. So to combine units with digits} \unit{299792458 meter inverse second} % en-route, but I'd like every three digits separated by a non-breaking space So try the digits command - two possibilities %\digit {\unit{299792458 meter inverse second}} % digits nests units - well the interpreter rejected this one %\unit{\digit{299792458} meter inverse second} % units nests digits - and this one. Conclusion digits and units don't play nicely together...unless someone has a nice solution Maybe a bit hard coding - fugly, but maybe... \unit{299~792~458 meter inverse second} % fails to interpret units, so no good 299~792~\unit{458 meter inverse second} % looks OK, but inelegant Now for trying to write in standard form..first the inelegant form, but giving a passable result Speed = 3 \times\ \unit{10^8 meter inverse second} But I'd guess this will not be inside a tex box, so the layout might be dodgy... numbers and units should not be split over two lines... A much more elegant solution would be: Speed = \unit{3e8 meter inverse second} % the documentation seems to support this, but not the practice... This one would be cleanly coded, if only the exponentiation worked... {\em spread of a physical quantity} One more, whilst I'm here. People will want to indicate a spread in a physical quantity, so: \unit{400\endash 700 THz} % inserts an unwanted space after the 400: ( 400 –700 THz). (cf 11\endash 14 , which 'behaves' as expected You can again kludge, by 400\endash \unit{700 THz} But elegant coding it ain't \ldots and again probably no bounding tex box, so may get split over two lines. \stoptext ___ KR Ian