Peter, I agree, the precision is 100 places.
Looking at Mathematica's result again, it appears to be formally incorrect. There is no binary point in front of the binary bits! Shouldn't the "-4" be "-104"?
Or does "RealDigits[0.036`100, 2, 100]" imply that one first multiplies .036 by 2^100. Then the answer is formally correct. That would really be confusing!
Bob
Yes, i understand, but the PRECISION (if I use the term correctly) is 100 places. Cheers, P. On 8/2/06, Bob Delaney <[EMAIL PROTECTED]> wrote:Peter, Because the "-4" means times 2^(-4), your result represents .036 accurate to 104 places following the binary point. BobI've often wondered about trying Maple (any good?). Anyway, here is a reply from Wolfram tech support, turns out I wasn't using Mathematica correctly (a common occurrence with me, not a simple app to use). Os other were correct, 0.036 is not base-2 representable, and this explains the integer round-down "error" first reported in this thread. ====== I believe Mathematica is working correctly. As specified in help of RealDigits, RealDigits[x]normally returns a list of digits whose length is equal to Precision[x]. Please use the correct precision.>RealDigits[0.036`100, 2, 100]returns: {{1, 0, 0, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 0, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1}, -4}_______________________________________________ Unsubscribe or switch delivery mode: <http://www.realsoftware.com/support/listmanager/> Search the archives of this list here: <http://support.realsoftware.com/listarchives/lists.html>-- ------------------------------------------------------------------------------- Peter K. Stys, MD Professor of Medicine(Neurology), Senior Scientist Ottawa Health Research Institute, Div. of Neuroscience Ottawa Hospital / University of Ottawa Ontario, CANADA tel: (613)761-5444 fax: (613)761-5330 http://www.ohri.ca/profiles/stys.asp ------------------------------------------------------------------------------- _______________________________________________ Unsubscribe or switch delivery mode: <http://www.realsoftware.com/support/listmanager/> Search the archives of this list here: <http://support.realsoftware.com/listarchives/lists.html>
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