2009/3/1 bill lam <cbill....@gmail.com>: > On Sun, 01 Mar 2009, Morten Welinder wrote: >> > After upgraded to 1.9.4. Diff the gnumeric file with the previous >> > 1.8.3 >> >> This is deliberate. We need to store enough decimals to ensure >> that the number we had will come back unchanged. The number > > This is incorrect. The number pairs have the same bit pattern using > ieee 754 standard so that they are equal.
No, it is correct, but you skipped this: "The number of decimals needed depends on what number we're trying to write, so we're just using the minimal number that fits all possible numbers." > From what I can see in your message, previous versions did not > deliberately find the minimum digit representation of floating point > number within the limit of ieee 754 standard. Correct. We need 17 digits for "double": welin...@toshiba:~/gnome/gnumeric> perl -e 'printf "%.17g\n", 1+2**-52;' 1.0000000000000002 welin...@toshiba:~/gnome/gnumeric> perl -e 'printf "%.16g\n", 1+2**-52;' 1 But, yes, for 5925.57 it would have been enough to use 16. We used to use 15 (I think), so we actually used to drop the occasional bit. Not Good[tm]. Somewhat embarrassing, in fact. Morten _______________________________________________ gnumeric-list mailing list gnumeric-list@gnome.org http://mail.gnome.org/mailman/listinfo/gnumeric-list
