On 20-ott-10, at 13:59, Lars T. Kyllingstad wrote:
On Wed, 20 Oct 2010 13:33:49 +0200, Fawzi Mohamed wrote:
On 20-ott-10, at 13:18, Lars T. Kyllingstad wrote:
[...]
However, I, like most people, am a lot more used to thinking in
terms
of
digits than bits. If I need my results to be correct to within 10
significant digits, say, how (if possible) would I use feqrel() to
ensure
that?
feqrel(a,b)>33 // 10*log(10)/log(2)
...which would be the solution of
2^bits = 10^digits,
I guess. Man, I've got to sit down and learn some more about FP
numbers
one day.
yes floating point use base 2 numbers: matissa + exponent both base 2.
feqrel gives you how many bits (i.e. base 2 digits) are equal in the
two numbers.
2^33=8589934592 which has 10 digits.
2^34 has already 11 digits, so having more than 33 binary digits in
common
means having more than 10 base 10 digits in common.
Thanks!
you are welcome
Fawzi
-Lars
