I have currently a Maple session running with only one open worksheet.

The worksheet only contains an input line with the name "a" and an output line with the name "a".

The fan of my laptop is running full throttle and the task manager displays 10% CPU usage and a very high power usage (3 mserver.exe running, the process with the cpu load is javaw.exe. Suspending this process shuts down the fan).

After about an hour I decided to ask. While typing this post (in Firefox, probably unrelated) the CPU usage went down and the fan went quite. The total system CPU usage is now down to 2%.

Has anybody seen the same? What could have cause it? It's not the first time I observe this. Anything that I could check before restarting Maple? All on Windows 10 after system restart.

Update:

The thread that consumes cpu is called ucrtbase.dll!configthreadlocate

Starting Maplesim in parallel almost immediately turns off the fan while the displayed cpu load is still high but now variing.

I can't understand why Maple interprets 1 .05  as 1 * 5 = 5 , and 2 .05  as 2 * 5 = 10 . Note the space between 1 and .05
In a different calculation I accidentally inserted a space between 1 and .05, and received a strange answer, and finally narrowed it down to a space.
But now I wonder why it is it is interpreting this way. Also I see that 2  0.05 produces an error. But  2 .05 is treated as 10. There is an implied multiplication? But the multiplication should be 2 * .05 , which is 1 and not 10.

i found thus condition which if we substitute in equation must be equal to zero, i don't know  how i can get zero

test_pde1.mw

I have encountered an issue: eq1 is not satisfied, though eq2 is satisfied for the parametric value (10). I need assistance in finding a way to ensure that both equations are satisfied simultaneously. Please provide guidance or suggest a potential approach for addressing this issue.verf_kk.mw

I have  a big problem in transformation How we can do suh transformation in  type of  procure  without use any hand work for example in physic abs|-| remove the exponential term how the maple remove that term automatically and collect all term and do my transformation this example is really hard one which is must do a lot by hand and mixed them which maybe a week take my time to get results and how i reach the results without spending that time i have a result of this equation and i am try to get but i don't know the results of this person is correct or not but i will share in here,  i did some try i will share in here too if in DEchange add U(xi) it will work and give me the other step but i need something more effective, when q^* is conjugate of q =exp(-ipsi(x,t))U(xi)

Download find_ODE.mw

How can I check if a name has been used/entered already but was not assigned to a value

The variable palette only lists assigned names.

I tried unames() but this lists all unassigned names. A 'user' option (which filters for user-assigned names) as in anames() does not seem to exist.

One of my failed attempts (in 1D-Math):

restart;
unames():
initial_unames := {%}:
new_name;
{unames()} minus initial_unames; # should ideally return a reduced set containing new_name;
has(%,new_name)

What else can be done? (I am probably overlooking something very simple.)

@Rouben Rostamian  

Dear Sir Professor Rostamian my name is Viorel Popescu from the Polytechnic University of Bucharest if you remember in the summer of 2019 you helped me to solve the equation: rH''(r)+H'(r)+(rk^2-r^2*b^2/R^2)H(r)=0 where k, b, and R are real constants positive number, with condition H(R)=0 and H'(1/R)=R. I appreciate it very much, please I'm in a similarly embarrassing situation to beg you for an answer. I want to find the equation of audion and complete the experiment http://www.michaelvio.byethost8.com/Audion.pdf

My account in Maple Primes is the same michaelvio (35) as the email michaelvio@yahoo.com and also @gmail.com it's an experiment that I want to make for my PhD. Practically I suppose that the energy can be approx. as a series of power of frequency t from I selected severaral terms Ea := 0.00762014687*t + a*t^2 + b*t^3 + c*t^4 + d*t^5 and I guess that satisfies an equation as in the document. The case of photons is beyond my possibility, but a little help from a distinguished Professor as you should cheer me up Audion1.mw

Audion.docx

Please help! 

Hello,

I noticed that the Linearly Implicit Euler method (also known as the Semi-Implicit Euler method) is not available in Maple's built-in ODE solvers. This method is useful for stiff ODEs, where part of the function is treated implicitly (for the linear term) and part is treated explicitly (for the non-linear term).

I know that the Linearly Implicit Euler method is a specialized method that probably does not find enough widespread use to justify its inclusion as a standard feature in Maple, especially given Maple's focus on numerical methods such as Runge-Kutta methods and fully implicit methods for rigid equations.

I’m wondering:

1. Why isn’t this method included in Maple’s standard set of numerical solvers?
2. How can I implement this method in my own code in Maple to solve stiff ODEs?

Any guidance or examples of implementation would be greatly appreciated!

Thank you!

Linearly_Implicit_Method.pdf

The usual ODE must be solved:
y´´*(y^3-y)+y´^2 *(y^2+1)=0
"Dangerous places" of the definition domain must be described: Where are the general solution y(x) and its derivatives continuous?

Could anyone help me to convert a code written in Mathematica to a Maple worksheet? I have PDF only. Could any one have a look on Mpale sheet and PDF....

Mathematica__to_Maple.mw

Mathematica_file.pdf

An animation only allows one time parameter.

I have an setup in which I have a time parameter + another parameter or more(e.g., offset, scale, whatever).

I would like some way to easily traverse phase space and see the result and animate with time at those specific parameters(ideally animate along any path in the phase space).

In my case what this means is that there is a 2D rectangle in which represents the phase space. E.g., time x offset. This effects the animation by setting the current parameters. If the animation is animated in time it moves across the vertical. Basically a "2d slider". Alternatively have actually 2(or more) independent sliders.

Currently I have to manually set the parameter then re-execute the animation to see the new animation.

e.g.,

  animation(plot, [f(t,offset)], t=0..1,offset=1..5)

How to use maple to compute the solution of two coupling equations that both have higher order derivatives? I used dsolve and couldn't solve it.

question928.mw

On my journey of discovery in the Maple world, which is new to me, I have now looked at the linear algebra packages. I am less interested in numerics than in symbolic calculations using matrices. I would like to illustrate this with the following task:

Let A be any regular (n; n) matrix over the real numbers for natural n. The regular (n; n) matrix X that solves the equation

X - A^(-1)*X*A = 0 for each A is to be determined. In this, A^(-1) is the inverse of A. Is there perhaps a symbolic solution for a specifically chosen n?

The solution to this old exercise is known. X is every real multiple of the unit/identity matrix, i.e. the main diagonal is occupied by a constant and all other matrix elements are zero.

Executing the code in ?InvertedPendulum produces an error when

sysLin := Linearize(convert(sysEqs, list), [u(t)], [x(t), theta(t)], lin_point)

is executed. The problem is the line where EQ4 is assigned a value.

Something is wrong with the line where EQ4 is assigned a value. It is not executed.
It is like the mode changes to text for that line????

I thought I had post with collection showing timelimit still hangs in Maple. But can't find it searching. I wanted to add this to it.

If someone finds such post, please let me know and I will append this to that post and delete this.

I just found another example where int() hangs all of Maple, using timelimit. I put timelimit of 30 seconds. After 2 hrs it is still running.

Maple 2024.1 on windows 10. This shows clearly that timelimit in Maple still does not work when It was supposed to have been fixed in Maple 2021?

For me, if there is anything that will make me stop using Maple for good, it is this timelimit issue.

Because with timelimit not working all the time, my program keeps hanging. It is not possible to do antything then. Having to keep checking if the program is still running or have hanged and restarting it is not a way to develop software.

Software that have been in development for almost 45 years now like Maple, should have figured by now how to implement timelimit that works. 

Note that, with smaller timelimit it is possible it will  not hang, because longer time limit makes it end in the code path which causes the hang. When I tried 5 seconds for example instead of 30 second, it did not hang With 30 it does. so if you try it and it does not hang, please increase the timelimit a little and it will surely hang. Just make sure to do restart each time, since Maple remembers last result.

maple's server.exe was running at full cpu also.

Download int_hangs_with_timelimit.mw

Update OCT 10, 2024

This is another example showing hang in Maple 2024.1 using timelimit. So adding it to this collection. I had large collection of such problems but not able to find it now.

I was trying to verify this solution (which could very well be wrong) on ode with IC. timelimit hangs when I added assumptions as shown. Used 10,20,30 seconds, and so on. all hang. Waited and waited. 

Does it hang on other systems? I am using Windows 10 and Maple 2024.1 with 128 GB RAM on fast CPU.

Download time_limit_hang_example_oct_10_2024.mw

I would like to officially offer $1,000 prize for any one who can solve the timelimit hanging problem in Maple. Will send you personal check of this amount if you find why it hangs and provide fix to use that I can verify works.