Unanswered Questions

This page lists MaplePrimes questions that have not yet received an answer

I'm working on a system of coupled ordinary differential equations with multiple degrees of freedom. I would like to explore the existence of multiple solutions by using a bifurcation diagram. To this end, I tried using the built-in Bifurcation command in Maple. However, the command repeatedly returns errors and fails to produce the expected plots.

Has anyone successfully used the Bifurcation command in Maple for coupled ODE systems? Are there specific settings or prerequisites that I might be missing? I would greatly appreciate any guidance or example code demonstrating how to properly use this command for such systems.
bifurcation.mw

To organize windows, Windows 11 provides a new function "Snap Layout". The example screen shot below shows options to place the Maple 2025 Screen Reader window.  

Ein Bild, das Screenshot, Reihe, Software, Multimedia-Software enthält.

KI-generierte Inhalte können fehlerhaft sein.

Draging now Maple 2025.1 Screen Reader to the left window of the third option results in the following selection screen

Ein Bild, das Text, Screenshot, Software, Computersymbol enthält.

KI-generierte Inhalte können fehlerhaft sein.

where on the right a list of tasks to chose from is presented. In this list Maple 2025.1 is missing. However Maple 2025.1 was running as can be seen from the task bar.

Has anybody managed to position Maple 2025.1 windows with the Snap Layout (or alternatively with Win+Arrow keys) or at least reproduce what I see on my computer?

Why can a Maple 2025.1 window be adjusted by hand but Windows does not do this in Snap Layout?

(Dragging and adjusting a Maple window by hand is not an option. This is how we had to work before Windows 7.)

How can I organize the KKT conditions I derived into a table format?

Can you confirm whether the substitutions I made for the lower and upper bounds are correct?

KKT_Table_Q-22.mw


For years I used to use 2 accounts when I am home

  • one under Firefox corresponds to my profesionnal account, which I can access to from my office oror home (and which is the one I use here),
  • the other one under Safari is my "personal" account; (login mmcdara)  which I cannot access to from my office because of security rules.
     

To separate the managing of professional and personal accounts I always used the former under Firefox and the latter under Safari.
Since the outage my personal account is no longer accessible, neither from Safari nor Firefox.

I created this account about eight years ago using the adress michael.mcdara@gmail.com and during all these years the connexion to Mapleprimes from Safari was  "automatic" in the sense that I was always logged in as mmcdara. Even after having quit Safari or shut down my computer, I was logged in as mmcdara as soon as I reopened Mapleprimes (a curiosity, for quitting Firefox being logged in as sand15 and openening it again required my relogging as sand15).

This still was the case early this morning (I sent replied to andiguy) but not one hour after.
Indeed Mapleprimes asked me my mail adress, that I knew, and my password, that I have forgot, of course.

Eight years ago the double authentification was not mandatory and so Gmail has purely and simply made the adress michael.mcdara@gmail.com inaccesible in between (I used it only with Mapleprimes, thus no real need to look at it regularly nor to bother with this double authentification stuff... at least I thought).
So any attempt to ask for a reinitialization of my password is a dead end for I cannot access the address michael.mcdara@gmail.com


My main activity on Mapleprimes is realized using my mmcdara account.
What bothers me the most  (loosing my mmcdara account would be unplesant but I can survive this) is that I was working since several months on two or three posts and that I can't anymore access the corresponding drafts (not a deadly situation I cannot survive to neither).

Do you have any idea about how to solve these issues?
I would satisfy myself recovering the two or three post drafts I was working on.

Thanks in advance
 

what is problem in here

restart;

with(plots):

with(LinearAlgebra):

with(DEtools):

diff(u(x), x) = f(u(x), v(x)), diff(v(x), x) = g(u(x), v(x)) for the two differential equations.

f := (u,v) -> u+cos(v);
g := (u,v) -> u*v-v+sin(v);

proc (u, v) options operator, arrow; u+cos(v) end proc

 

proc (u, v) options operator, arrow; v*u-v+sin(v) end proc

(1)

The equilibria:

equilibria := solve({f(u,v)=0, g(u,v)=0}, {u,v},explicit);

{u = 1, v = Pi}, {u = -cos(RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z)), v = RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z)}

(2)

allvalues(RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z))

RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z, 1.306542374), RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z, -1.306542374), RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z, -2.331122370), RootOf(sin(_Z)*_Z^2+sin(_Z)-2*_Z, 2.331122370), 0

(3)
 

NULL

Download remove.mw

i want plot a system of differential equation and do phaseportrait i did but when i want make it a little bit more clear and colorfull like rainbow when i find the C.Q i don't know how set the option for ploting?

e1.mw

In a recent MaplePrimes question: https://mapleprimes.com/questions/240543-Maple-20251-On-Windows-11-How-To-Resize 

a discussion of interrupting a computation also came up.

I gave some comments. In one of these I wanted to include a link to a screenshot. 
I tried several times. It seemed that I only had the choice between the full image or a thumb nail.
So I chose the latter. That appeared to me as worthless. I tried a couple of times more, but decided to delete all 3.

Then I wrote a comment without a screenshot. 

It looks silly to have these empty (and anonymous) "comments" still around.
Is there any way to remove these?

Maple 2024 had a very well defined "Stop Execution" symbol on the desktop.  

Maple 2025 doesn't have an obvious symbol somewhere.  Also, the two little "dots" that I once had in the lower left bottom in Maple 2025 have disappeared! There is only a bar at the bottom which seems to do nothing.

Someone should please help me compute the left and right eigenvectors of the system below. The purpose is to compute values for 'a' and 'b' in the bifurcation formula.

Thank you

``

with(VectorCalculus)

 

(1)

interface(imaginaryunit = I)

I

(2)

I

I

(3)
 

diff(S(t), t) := `Λ__p`-(`#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("θ",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`/N[p]+µ__C)*S+`ω__B`*I__B

Lambda__p-(`#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("θ",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`/N[p]+µ__C)*S+omega__B*I__B

(4)

diff(I__B(t), t) := `#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("θ",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`*S/N[p]-`ω__B`*I__B-(`σ__B`+µ__C)*I__B

`#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("θ",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`*S/N[p]-omega__B*I__B-(sigma__B+µ__C)*I__B

(5)

NULL

``

(6)

diff(S__A(t), t) := `Λ__A`-(µ__A+`#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("α",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`/N[p])*S__A+`δ__A`*I__A

Lambda__A-(µ__A+`#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("α",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`/N[p])*S__A+delta__A*I__A

(7)

diff(I__A(t), t) := `#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("α",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`*S__A/N[p]-(µ__A+`δ__A`)*I__A

`#mrow(mi("ϕ",fontstyle = "normal"),mo("⋅"),msub(mi("α",fontstyle = "normal"),mi("B")),mo("⋅"),msub(mi("I"),mi("B")))`*S__A/N[p]-(µ__A+delta__A)*I__A

(8)

NULL

``

(9)

Download CBD2.mw

Same question for googletagmanager.

The NoScript extension for Firefox lists the following java scripts

I do not see a degradation in performance when these scripts are disabled. So why are these scripts running?

What do they do?

It is not difficult to manually check the validity of the identity  sqrt(x+2*sqrt(x-1)) = sqrt(x-1)+1 , which is true at least for all  x>=1 . I don't know of any Maple command that directly makes this simplification:

expr:=sqrt(x+2*sqrt(x-1));
simplify(expr);
simplify(expr) assuming x>=1;

                          


It was possible to simplify it only by making a variable substitution  x=y+1 (and then a reverse substitution  y=x-1 ) :

expr1:=subs(x=y+1,expr);
simplify(expr1);
subs(y=x-1, %);

                               


By the way,  the CAS Mathematica also cannot cope with simplifying the expression  expr .

Wondering what the experts here think of this. Should not simplify have worked on this automatically? By trial and error, found that combine command is what simplified it the best.

But I think simplify should also have done the same.  

Interested to hear what others think, and why simplify (even using trig option) did not do it.   

The issue is that this is done in code, without lookin at the screen and deciding what to do based on what the expression "looks like".

interface(version);

`Standard Worksheet Interface, Maple 2025.0, Linux, March 24 2025 Build ID 1909157`

A:=(((sin(sqrt(3)/2)*sqrt(3) - 3*cos(sqrt(3)/2))*cos(sqrt(3)*x/2) - sin(sqrt(3)*x/2)*(sqrt(3)*cos(sqrt(3)/2) + 3*sin(sqrt(3)/2)))*exp(-1/2 + x/2))/3 ;

(1/3)*((sin((1/2)*3^(1/2))*3^(1/2)-3*cos((1/2)*3^(1/2)))*cos((1/2)*3^(1/2)*x)-sin((1/2)*3^(1/2)*x)*(3^(1/2)*cos((1/2)*3^(1/2))+3*sin((1/2)*3^(1/2))))*exp(-1/2+(1/2)*x)

B:=- exp(-1/2 + x/2)*(sqrt(3)*sin(sqrt(3)*(x - 1)/2) + 3*cos(sqrt(3)*(x - 1)/2))/3;

-(1/3)*exp(-1/2+(1/2)*x)*(3^(1/2)*sin((1/2)*3^(1/2)*(x-1))+3*cos((1/2)*3^(1/2)*(x-1)))

simplify(A-B); #show these are same

0

simplify(A,trig)

-(1/3)*((-sin((1/2)*3^(1/2))*3^(1/2)+3*cos((1/2)*3^(1/2)))*cos((1/2)*3^(1/2)*x)+sin((1/2)*3^(1/2)*x)*(3^(1/2)*cos((1/2)*3^(1/2))+3*sin((1/2)*3^(1/2))))*exp(-1/2+(1/2)*x)

simplify(A)

-(1/3)*((-sin((1/2)*3^(1/2))*3^(1/2)+3*cos((1/2)*3^(1/2)))*cos((1/2)*3^(1/2)*x)+sin((1/2)*3^(1/2)*x)*(3^(1/2)*cos((1/2)*3^(1/2))+3*sin((1/2)*3^(1/2))))*exp(-1/2+(1/2)*x)

simplify(A,size)

-(1/3)*((-sin((1/2)*3^(1/2))*3^(1/2)+3*cos((1/2)*3^(1/2)))*cos((1/2)*3^(1/2)*x)+sin((1/2)*3^(1/2)*x)*(3^(1/2)*cos((1/2)*3^(1/2))+3*sin((1/2)*3^(1/2))))*exp(-1/2+(1/2)*x)

simplify(normal(A))

-(1/3)*((-sin((1/2)*3^(1/2))*3^(1/2)+3*cos((1/2)*3^(1/2)))*cos((1/2)*3^(1/2)*x)+sin((1/2)*3^(1/2)*x)*(3^(1/2)*cos((1/2)*3^(1/2))+3*sin((1/2)*3^(1/2))))*exp(-1/2+(1/2)*x)

combine(A); #finally

(-(1/3)*3^(1/2)*sin((1/2)*3^(1/2)*(x-1))-cos((1/2)*3^(1/2)*(x-1)))*exp(-1/2+(1/2)*x)

 

 

Download simplify_vs_combine_june_4_2025.mw

Hello, 

I'm working on a Maple package that manages external processes via TCP connections. I'm using ModuleUnload for cleanup, but I need to better understand how it behaves during Maple termination.

The issue:
- I have a module that manages external processes (via TCP connections)
- I implemented ModuleUnload to kill these processes when the module is unloaded
- ModuleUnload works perfectly when using 'restart' 
- However, when closing the Maple window, the external processes remain active

Investigation:
Using 'lsof', I observed that:
   - When Maple closes, it properly closes its TCP connection (goes to CLOSE_WAIT state)
   - But the external processes remain active

Questions:
1. Is this the expected behavior of ModuleUnload during session termination?
2. Are there alternative approaches to ensure cleanup when Maple is closed?

Any insights or suggestions would be greatly appreciated!
Thanks!

I used Maple’s odetest to check the validity of 36 exact solutions.

About half of them return zero, meaning they satisfy the ODE correctly. But the other half don’t — odetest gives nonzero expressions.

My question is:

Could there be a mistake in my assumptions, or are some of these solutions only valid under specific conditions?

I’d appreciate any clarification or suggestions.

ode-test-36.mw

Respected sir,

I sincerly apologize to take your valuable time.

kind help with construction of function for the question in the word file attached.

Kind help please it may be simple too.

Kind_help.pdf

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