David Roe wrote :
I posted a patch there that should fix it; I have to work on other
stuff, but if someone else wants to take over and write some doctests,
make sure it works in lots of cases...
David
On Mon, Oct 25, 2010 at 17:14, Burcin Erocal bur...@erocal.org
mailto:bur...@erocal.org
On Tue, Oct 26, 2010 at 1:03 AM, Francois Maltey fmal...@nerim.fr wrote:
David Roe wrote :
I posted a patch there that should fix it; I have to work on other stuff,
but if someone else wants to take over and write some doctests, make sure it
works in lots of cases...
David
On Mon, Oct 25,
Hi
while calculating the integer part of square roots I realized that
sqrt() returns wrong results for large inputs (although the sqrt()
command itself accepts bignum values).
example: int(sqrt(2^94533))
I guess that this is due to the fact that SAGE simplifies the
expression above as sqrt(2) *
Georg wrote :
while calculating the integer part of square roots I realized that
sqrt() returns wrong results for large inputs (although the sqrt()
command itself accepts bignum values).
example: int(sqrt(2^94533))
int isn't a mathematical Sage type, but Integer is a Sage type.
And Integer
When you do sqrt(2^m) when m is odd, say m=2*k+1, the returned value
is symbolically 2*k * sqrt(2):
sage: sqrt(2^101)
1125899906842624*sqrt(2)
Now using Integer() to round that will evaluate sqrt(2)
approximately to standard precision, which is not enough. Instead,
use the isqrt() method for
This is a good workaround, but the original problem can be traced to the
function sage.symbolic.expression.Expression.__int__
def __int__(self):
#FIXME: can we do better?
return int(self.n(prec=100))
Presumably you could adaptively estimate to higher precision until your
error interval
On Mon, 25 Oct 2010 17:00:39 -0400
David Roe r...@math.harvard.edu wrote:
This is a good workaround, but the original problem can be traced to
the function sage.symbolic.expression.Expression.__int__
def __int__(self):
#FIXME: can we do better?
return int(self.n(prec=100))
I posted a patch there that should fix it; I have to work on other stuff,
but if someone else wants to take over and write some doctests, make sure it
works in lots of cases...
David
On Mon, Oct 25, 2010 at 17:14, Burcin Erocal bur...@erocal.org wrote:
On Mon, 25 Oct 2010 17:00:39 -0400
David
