Items tagged with mapleprimes mapleprimes Tagged Items Feed


Thank you very much for your idea in previous discussion: this is the link.

I asked how can I plot the phase portrait of this system

Sys1 := {diff(r(t),t) = r(t)^2*sin(theta(t)), diff(theta(t),t) = -r(t)^2*(-2*cos(theta(t))^2+1)};

I get this answer:


1) For me it's not necessary to give an initial condition to plot the pharse portrait.

2) What is the line in this phase portrait.

3) Here, I try a second method using Matlab code, I get:


and this is the code:

[r, theta] = meshgrid(0:pi/4:2*pi, 0:pi/4:2*pi);
rdot =r.^2.*sin(theta) ;
thetadot = r.^2.*(1-2*sin(theta).^2);

the arrow in the phase portrait are not the same.

Can someone give me more clear information about this problem.

Many thinks.


I'm not being notified anymore about responses to answers or comments to MaplePrimes. I'm assuming that I'm not the only one (?). This has happened before.

Hi all. I am using Maple 18.

1. How can I make maple NOT plot discontinuties with a vertical line? For example, plotting y=tan(x) displays vertical lines. Is there a setting to turn this off permanently?

2. When I type y=sin(x-Pi/2) and press enter, y = -cos(x) is displayed in blue. I am sure they are both the same thing, but I would like to see the expression that I typed, not an alternate expression that Maple wants to display.

3. Why do some expressions require a ; at the end, whilst others don't? Ie. y = sin(x) and y = 1+sin(x) do not, but y=2*sin(x) results in a "Warning, inserted missing semicolon at end of statement"

4. Is there a section on Mapleprimes(this site) where new users can ask questions? I would like to browse it to see what sort of problems other new Maples users have encountered. I am sure that my above questions may have been asked a few times over the years by newbies like myself.

Thanks in advance. :)

hi,i can not upload anything to every time i want to upload a file, i face error generating page . what should i do ?! 

Yesterday afternoon, we updated MaplePrimes. The purpose of the update was primarily to squash some bugs and improve user experience.

Highlights of the update include:

  • The ordering of replies has been corrected, as described in this post by Carl Love.

  • We fixed a problem whereby some members were unable to attach a file to a question or post.

  • Flagging a comment now works correctly.

  • Broken images that were appearing on some of our older posts have been restored. In addition, some older posts had incorrect dates, and these have been restored.

  • Some embedded links to user profiles or messages were resulting in errors, and have been corrected.

  • After receiving a badge, members will now be notified via a pop-up message.

A number of other small improvements were made as well.

As always, thank you for letting us know when you encounter a problem, and please continue to do so. We take note of everything that you report, and we try our best to prioritize and take care of the issues.


For some time I have been running into the problem where uploaded worksheets that are inlined into a Mapleprimes post get gridlines shown, even when they are not specified or shown in the original worksheet. This is a problem because quite often the gridlines make an inlined plot unattractive.

I believe that Mapleprimes uses some version of MapleNet as a mechanism for inlining uploaded worksheets.

It seems that the Standard GUI and/or MapleNet have special handling for gridlines in the sense that they actually distinguish between PLOT structures generated without the `gridlines` option versus those created with `gridlines=false`.  I believe that this has something to do with the persistence of various plot qualities in an output region which (perhaps for historical reasons?)  allow re-execution of a plot input command to produce a plot output rendering that remembers whether gridlines are visible.

If the second plot below does indeed get rendered here in Primes without gridlines visible then one workaround is evident: adding `gridlines=false` instead of omitting the option.





I'll submit a bug report against MapleNet.


why does not send me email notifications ?! could anyone help ? i do not receive email notification of related posts.

Dear Bryon and Will:

Please fix MaplePrimes so that the Replies to Answers to Questions appear in chronological order under their respective Answers. Currently they appear in a somewhat random and changing order when their are several Replies. This has been a problem since the last "upgrade" to MaplePrimes.

Another persistent problem since that upgrade is that about half of the time that someone tries to attach a file, the file does not actually attach, even though the editor gives every indication that it has attached, and a hyperlink even appears in the post.

People are starting to leave MaplePrimes because of these problems.

Thank you for your attention to these matters,
Carl Love

Dear friends. 

This is to alert you to a minor problem with your website. I use a variety of operating systems and browsers to access your site. With Firefox 22 and Firefox 26 and OpenSuse 12.2 when I click on a question with a lot of commentary like "Perl vs. Maple (MPF)" from a couple of days ago or "collect x/2-y/2 1/2" the question appears to load for a while but then an empty page appears, containing only the string "2014" and nothing else. Maybe you want to look into this.

Best regards,

Marko Riedel


Who was the creator of Maplesoft?

I have noticed that Maple's command isolve doesn't always seem to work for me. An example would be solving

x^2 + y^2 +z^2 =3 over the integers. Maple does not return any solutions.

I have found that isolve work for two variables, so I have just been iterating the third variable and applying isolve. However what if I want to solve  something with negative coefficients like : x^2 +y^2 +2*z^2 +x*y -y*z, then I have to be careful about which variable I iterate and the bounds are not always obvious.

Is there an easy fix to solve a homogeneous degree 2 polynomial in three variables over the integers ? Thanks!

There are still several bugs resulting from the MaplePrimes update last week which you may not be aware of.

  1. The list "All Recent Posts & Questions" is not in the correct order. It is ordered by the time of creation of the Post or Question. It should be ordered by the time of the most recent update to the thread. In other words, the top seven entries in "All Recent Post & Questions" should be the seven entries of "Active Conversations".
  2. Email notifications do not always contain a hyperlink to the relevant post. (I could send you some examples if you need.)
  3. In the list of Answers in a user's profile, the votes for the Answers are not shown for those Answers created after the update.
  4. There are no longer automatically generated titles for Replies for which the author fails to enter a title. This taken alone may be a good idea, but it contributes to bug (2) above. Also, it makes it impossible to send a "Contact Author" email relating to the Reply---when you click send on the email, it will be rejected, even if you tried to add a title.

MaplePrimes status...

October 25 2013 Bryon 1048 MaplePrimes

Earlier this week, we updated MaplePrimes with some fairly extensive changes that improved site performance. While MaplePrimes behaved as expected for most, a few people experienced some problems logging in, and a few other issues were also reported. If you are a MaplePrimes member inconvenienced by these issues, I apologize and thank you for your patience, and also for reporting the problems. I've had some conversations with a few different members, and your help in describing and diagnosing the problems is very much appreciated.

We have been working hard to resolve these problems, and I'm happy to report that most have now been taken care of.

  • The log-in function now works as expected across all browsers. If you are still having problems, you can visit to force a log-out and reset your browser cookies for MaplePrimes, which will also correct the problem going forward.

  • We have corrected the problem where links to uploaded files were resulting in 404 errors.

  • We have also corrected an issue where the ordering of posts in a user's profile page was done incorrectly.

There are a handful of smaller problems that we continue to work through, and if you notice any other issues, please continue to let us know, either by posting here on MaplePrimes, or by contacting me directly.


The board is going to work now with FF for me after latest updates.

NB: I got some mails advicing to delete (old) cookies for Mapleprimes, but
as my browser is alsways completely cleared on close (or on demand) that can
not have been the reason.

It works at least, if I give up all security settings. Which I do not want,
so I sketch a way to use them.

Be aware that not all in a page comes from Mapleprimes. Some is from another
server and thus considered as 3rd party. Same for some scripts
and CSS etc, which stem from Google, jquery (or else)

If using NoScript or some blockers or similar essentially one has to allow, which was needed in the previous version as well (see
below). Dito is needed (both are 3rd party to Mapleprimes).

It still may hang up at loading ajax-loader.gif, which is located on the
server - I do not know why. After allowing a request policy
from to it loads.

That allows to still block all the social media stuff (especially FB connect
is disabled)

And currently I do not see calls to 2o7, just Omniture is trying to work.


For the call to Google: it seems to be needed only for their jquery library, and .../jquery/.

But the site calls the open source anyway. So why using
Google as well? Why not change and stay on

Calling to Google transmits my IP and browser header, it is like a fingerprint
and allows GG to identify me later on as Maple user. I dislike that very much.

Edited: edit works as well

After disabling all security addons the Ajax gif loads, then it shows an error and after that it jumps to a page displaying "2013", but that page actually does not have any content (use ctrl + u to see it).

And the I see, that the browser tries to load from and hangs up in that transfer (have not checked the ports).

In reality I would forbid to load from 2o7, as I receject almost all trackers.

But looking at Adobe or others those are 3rd party cookies (Omniture ---> Adobe)

Every reasonable person aware of security and xss forbids dubious sources from other websites (and I am not happy that this sites call Ajax at Google)

And if that is the reason for the bad behaviour of the new sites it would be a good joke, really.

For me it only works with IE and all its security issues (and I have to use "preview" before posting is possible)

1 2 3 4 5 6 7 Last Page 1 of 76