ned notion of
positivity, checking if something is > 0 feels like the right duck-typing
thing to do. I guess I'll try some other way.
On Saturday, June 27, 2020 at 12:40:54 AM UTC-10, Dima Pasechnik wrote:
>
> On Sat, Jun 27, 2020 at 10:38 AM Rob H. >
> wrote:
> >
&
Hi all,
So I was surprised to find out that asking if a polynomial is > 0 doesn't
raise an error. Now, maybe there's a good reason why it returns True and
I'm too tired to think about why. At the very least, here is some
disturbing behaviour.
sage: R. = PolynomialRing(QQ)
sage: x > x-1
True
Hi,
I have
sage: var('A,B')
sage: assume(A>1)
sage: assume(B>A)
sage: bool(2*B>A)
False
Now, I know it's that sage considers 2*B and A incomparable, not that it
actually thinks that 2*B <= A. And similarly,
sage: bool(B > A - 10)
False
Is this really something sage (i.e. maxima) can't handle?
Hi.
The referee for a paper I've submitted has asked us to provide some brief
remarks on both the time *and space* taken for the various examples we
provide for our code. A lot of people talk about benchmarking time, so I'm
not really asking about that here (though if you think using default_ti
Hi,
I tried logging in to trac and my credentials were refused. Acknowledging
it was possible that I changed my password a while back and forgot, I reset
my password. The password sent to me by email also doesn't work. Is the
login system down?
Thanks,
Rob
--
You received this message becau
r time.
Best,
+Rob
On Nov 4, 5:23 pm, luisfe wrote:
> On 2 nov, 17:00, "Rob H." wrote:
>
> > Hi,
>
> > so here is some sample code:
>
> > var('chi,k')
> > R.=SR[]
> > I=R.ideal(x^2)
> > Rbar.=R.quotient_ring(I)
> > expr=Rba
Here's another simple example of basic simplifications that aren't
processed:
P.=SR[]
F=P.fraction_field()
print F(x/x)
print simplify(F(x/x))
Output:
x/x
x/x
Does anyone have any suggestions on how to fix/circumvent these
problems?
Thanks,
+Rob
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Hi,
so here is some sample code:
var('chi,k')
R.=SR[]
I=R.ideal(x^2)
Rbar.=R.quotient_ring(I)
expr=Rbar(epsilon-(chi^(k-1))^5+chi^(2*k-2)*(chi^(k-1))^3)
view(expr)
print (expr)
exprnice=simplify(expr)
view(exprnice)
exprnice2=simplify(expand(expr))
view(exprnice2)
exprnice3=expand(simplify(expr))
Hi,
I'd like to know whether I can invert a specific element a of a
(commutative) ring R, and I'm fine with adding that inverse to the
ring if possible. For example, can I construct the ring ZZ[1/2] ?
ZZ.extension(2*x-1,'alpha') doesn't work since the polynomial must be
monic. Obviously, if R is a
