Yes, and I should have thought of that!
Fernando
On 3/5/2020 12:13 PM, Dima Pasechnik wrote:
In fact, substituting x and y directly into the equation of the curve
to plot, and clearing denominators,
produces something pretty good,IMHO:
More conceptually, one can use, with care, Sage's substitution facilities:
sage: var('u v x y t');
sage: f=y^2-x^3+x
sage: fs=(f.subs(x=u*3*t^(-1/2),y=v*3*t^(-1/2))*t^(3/2)).expand() #
only works with extra variable t
sage: implicit_plot(fs.subs(t=1-u^2-v^2),(u,-1,1),(v,-1,1))
On Thu, Mar 5, 2020
In fact, substituting x and y directly into the equation of the curve
to plot, and clearing denominators,
produces something pretty good,IMHO:
implicit_plot(v^2*3*sqrt(1-u^2-v^2)-u^3*9+u*(1-u^2-v^2),(u,-1,1),(v,-1,1))
On Thu, Mar 5, 2020 at 4:51 PM Dima Pasechnik wrote:
>
> On Thu, Mar 5, 2020
On Thu, Mar 5, 2020 at 2:32 PM Fernando Gouvea wrote:
>
> This works, in the sense that there's no error. One does get a bunch of
> extraneous points near the boundary of the disk. It's as if plot_points were
> trying to connect the point at (0,1) and the point at (0,-1) along the
> circle,
This works, in the sense that there's no error. One does get a bunch of
extraneous points near the boundary of the disk. It's as if plot_points
were trying to connect the point at (0,1) and the point at (0,-1) along
the circle, even though f_uv is 1 on the circle.
Strangely, they occur only
On Wed, Mar 4, 2020 at 12:20 AM Fernando Gouvea wrote:
>
> But no, it doesn't work, since it gives a rectangular plot instead of one in
> polar coordinates. But maybe we are closer.
I looked at the labels on the axes, and they do match the ranges of r
and phi, so I don't udnerstand
how it's
But no, it doesn't work, since it gives a rectangular plot instead of
one in polar coordinates. But maybe we are closer.
I still think implicit_plot should be smarter about values that do not
make sense.
Fernando
On 3/3/2020 6:26 PM, Dima Pasechnik wrote:
even better:
sage: var('x y u v r
Nice idea. Thanks.
Fernando
On Tue, Mar 3, 2020 at 6:27 PM Dima Pasechnik wrote:
> even better:
>
> sage: var('x y u v r phi')
> : u=r*cos(phi)
> : v=r*sin(phi)
> : x=u*sqrt(9/(1-r^2))
> : y=v*sqrt(9/(1-r^2))
> : implicit_plot(y^2-x^3+x==0,(r,0,999/1000),(phi,-pi,pi))
>
>
even better:
sage: var('x y u v r phi')
: u=r*cos(phi)
: v=r*sin(phi)
: x=u*sqrt(9/(1-r^2))
: y=v*sqrt(9/(1-r^2))
: implicit_plot(y^2-x^3+x==0,(r,0,999/1000),(phi,-pi,pi))
On Tue, Mar 3, 2020 at 10:28 PM Dima Pasechnik wrote:
>
> On Tue, Mar 3, 2020 at 10:10 PM Fernando
On Tue, Mar 3, 2020 at 10:10 PM Fernando Gouvea wrote:
>
> The whole point of this is to show the behavior of the curve near infinity,
> so changing the limits is not an option.
just paste together a number of rectangles where (u,v) stay inside the
unit circle.
(yes, this would need writing a
A caveat is that at the boundary, the mapping you describe becomes
non differentiable (the determinant of the differential blows up to
infinity),
so it's going to be painful for implicit_plot to work.
That being said, the following tweak runs ok but it's not
The whole point of this is to show the behavior of the curve near
infinity, so changing the limits is not an option.
Fernando
On 3/3/2020 4:15 PM, Dima Pasechnik wrote:
On Tue, Mar 3, 2020 at 8:20 PM Fernando Gouvea wrote:
Here's what I ended up trying, with r=3:
var('x y u v')
On Tue, Mar 3, 2020 at 9:15 PM Dima Pasechnik wrote:
>
> On Tue, Mar 3, 2020 at 8:20 PM Fernando Gouvea wrote:
> >
> > Here's what I ended up trying, with r=3:
> >
> > var('x y u v')
> > x=u*sqrt(9/(1-u^2-v^2))
> > y=v*sqrt(9/(1-u^2-v^2))
> > implicit_plot(y^2-x^3+x==0,(u,-1,1),(v,-1,1))
> >
> >
On Tue, Mar 3, 2020 at 8:20 PM Fernando Gouvea wrote:
>
> Here's what I ended up trying, with r=3:
>
> var('x y u v')
> x=u*sqrt(9/(1-u^2-v^2))
> y=v*sqrt(9/(1-u^2-v^2))
> implicit_plot(y^2-x^3+x==0,(u,-1,1),(v,-1,1))
>
> That gives an error:
>
>
On 12/29/2016 04:46 AM, Fjordforsk A/S wrote:
> Thanks Michael. I am plotting it now, and it is just waiting without giving
> a crash.
> Is it automatically right to use complex_plot command to plot the imaginary
> part of the same plot as given below?
>
It depends, do you expect your
Thanks Michael. I am plotting it now, and it is just waiting without giving
a crash.
Is it automatically right to use complex_plot command to plot the imaginary
part of the same plot as given below?
onsdag 28. desember 2016 16.58.00 UTC+1 skrev Michael Orlitzky følgende:
>
> On 12/28/2016
On 12/28/2016 10:33 AM, Fjordforsk A/S wrote:
> This is how its supposed to go:
>
> sage: plot3d(((1 - (3/8 - 3*t^2 - 2*t^4 - 9*x^2 - 10*x^4 - 12*t^2*x^2) +
> i*x*(15/4 + 6*t^2 - 4*t^2 - 2*x^2 - 4*x^4 + 8*t^2*x^2))/(1/8*(3/4 + 9*t^2 +
> 4*t^2+ 16/3*t^6 + 33*x^2 + 36*x^24 + 16/3*x^6)))*e^(i*x)),
For what it is worth, this works fine in SageMathCloud
https://cloud.sagemath.com/projects/4a5f0542-5873-4eed-a85c-a18c706e8bcd/files/support/2016-10-31-083851%20polyhedron.sagews
which you can easily run locally via Docker:
On Sun, 18 Sep 2016, jack wrote:
Ubuntu16.04.
P=plot(log((1+x)/(1-x)), (x, -1,1))
show(P)
gives a lengthy error message which ends with
ImportError: cannot import name scimath
I installed sage at /home/jack/Tools
One clue might be the initial message I get on initiating sage in a
On 27/04/12 21:55, Jason Grout wrote:
On 4/27/12 2:38 PM, Jose Guzman wrote:
On 27/04/12 20:52, Jason Grout wrote:
On 4/27/12 10:15 AM, Jose Guzman wrote:
Dear colleagues,
I am trying to manipulate an expression that starts at a time =
tonset. Everything works nice until I try to plot.
Yes, exactly!
Thank you Jason:
Th
- Original Message -
From: Jason Grout
To: sage-support@googlegroups.com
Sent: Thu, 23 Feb 2012 10:46:44 -0600
Subject: [sage-support] Re: Plotting untouched linear system
On 2/23/12 10:30 AM, btho...@nexus.hu wrote:
Hello,
For clarity reasons, in
I have made a few months ago the upgrade of mayavi experimental spkg to version
3.5,
I forgot the ticket info now (you can search it by the name
ets-3.5.0-20101024.p0.spkg), to install it you have to
follow the guidelines in Jaap's page:
http://sage.math.washington.edu/home/jsp/SPKGS/ETS,
Em 04-04-2011 19:07, achrzesz escreveu:
sage: plot(lambda w:arg(1/(I*w) + 1/2 + (I*w)) ,(w,0,5),
axes_labels=['$Frequency$', '$Phase$'])
Works. Thanks!
--
Renan Birck Pinheiro - Grupo de Microeletrônica - Eng. Elétrica/UFSM
http://renanbirck.blogspot.com | http://twitter.com/renan2112
skype:
On Mon, Jan 18, 2010 at 12:14 AM, Simon King simon.k...@nuigalway.ie wrote:
Hi!
On Jan 17, 10:57 pm, William Stein wst...@gmail.com wrote:
[...]
Is there a way to *fix* the y-axis to the range [-2, 3.5] in the above
example?
Do this:
It's pretty annoying that the input you give above
On Jan 9, 2010, at 7:51 PM, Marshall Hampton wrote:
I could be wrong but that problem might relate to the fact that
plotting is often done in floats, which can't handle quantities like
15^1024. Other types in Sage can handle such things, so you might
have to work around that limitation by
Hello,
This bug feels very similar to 7614 (not 7165) and so 5572.
http://trac.sagemath.org/sage_trac/ticket/7165
--
To post to this group, send email to sage-support@googlegroups.com
To unsubscribe from this group, send email to
sage-support-unsubscr...@googlegroups.com
For more options,
On Sun, Dec 6, 2009 at 4:51 PM, Michel vdbe...@gmail.com wrote:
Thanks for the reply. But no. The problem is not due to the fact that
the function has a singularity. Indeed.
plot(20*log(abs((1+I*x)^4),10),(x,0,3))
fails with the same error which is incomprehensible to me.
On the other hand
27 matches
Mail list logo
