I only have Maple 2025.2 on this new PC. Could someone just run this code on earlier Maple version and see if they get same crash?

I am finding many crashes in Maple 2025.2 (3 so far) and I am only 25% in my test.  But not sure if this is new or was there in Maple 2025.1 or earlier. 

I am trying to document all the new problems in Maple 2025.2.

Here is the worksheet (save all your work just in case).

Download maple_crash_odetest_2025_2_nov_26_2025.mw

I am trying to see if installing Physics update package will fix a problem I am having as described here by having a fix that maybe not included in Maple 2025.2

But I do not know how to do that. When doing Physics:-Version(); or Physics:-Version(latest); Maple says

             `The "Physics Updates" package is not available for the version of Maple under development`

Does this mean Physics update package is not needed in Maple 2025.2?  Otherwise, what are the instructions to install Physics package now?

May be someone could clarify the status of Physics package and if it is something that one should still install along with SupportTools which in Maple 2025.2 was there automatically and did not need to install it.

Update 

JUst verified that Physics update package V 1881 is still needed in Maple 2025.2 as it has important fixes not merged in Maple 2025.2.

To install Physics package in Maple 2025.2 had to click on the top right corner of the worksheet (the down arrow) near the "sign in".

Then go down to "packages" and select and click on the install button next to Physics package.  (first in list).

This will download and install it.

Now closed all of Maple and restarted it.

Now Physics package V 1881 is installed and have fixes in it that are missing from Maple 2025.2.  This is why my test was failing. Now the test do not fail.

So first time, the command Physics:-Version(latest) does not work. But from now on it should work.

I would have expected all fixes made in Physics update to have been merged into the new Maple release.

In 2025.2, I found that calling Physics:-Setup causes code of `convert/diff` to change (on the fly) causing error.

I removed from my code the places I was calling Physics:-Setup explicitly, but the error still shows up. Which means there is still places in the code to cause Physics to come into play.

I just installed 2025.2 and have not done anything yet. Just running a test. 

Does one need to install Physics package?

First, let me give an example showing that calling Physics:-Setup changes `convert/diff` which ends up causing an internal Maple error

Download why_code_changes_calling_Physics_maple_2025_2_nov_24_2025.mw

Notice that now calling PDEtools:-difforder(convert(T,diff))  fail because Physics:- was called.

But my code now has no calls to Physics:-, I made sure to comment all those out. 

But I still get same error when I run my test program. Not able to find where Physics is "activated" again to cause the code change in `convert/diff` that happens dynamically when Physics is loaded.

It must be happining on different call internally. But have no idea why and where.

This is all on new PC. I have no Maple ini files or anything like this that can cause this.

Will installing Physics package explicity fixes this?   

Update

I think I know why this happens. Not all fixes made by Edgardo S. Cheb-Terrab in last Physics update are included in Maple 2025.2 !

See https://mapleprimes.com/questions/240843-Why-PDEtoolsSolve-Fail-On-This-Equation  where fix is made in Physics  v.1880 which I confirmed in Maple 2025.1.

But now I checked and this problem is back in Maple 2025.2. which means that fix was not merged into Maple 2025.2. How could this happen?

Download fixed_in_2025_1_but_missing_in_2025_2.mw

So I am hoping that figuring how to install Physics update in Maple 2025.2 will fix the current problem with convert and also bring that old fix for PDEtools:-Solve back into Maple 2025.2.

This is something that Maplesoft should have taken care of.

Update 

Figured how install Physics update package V 1881 and doing so fixed this problem in Maple 2025.2 !

This tells me that all fixes that were in Physics update package were not merged into Maple 2025.2

This worksheet shows that now code works OK, but need to make sure to install Physics update package in Maple 2025.2

Download why_code_changes_calling_Physics_maple_2025_2_nov_24_2025_V2.mw

I cannot get the ini file to load packages.  It executes fine and the bottom commands work, but the package does not load.
Is there some special way to load packages in the ini file?

Thanks!

with(LinearAlgebra):
    stoperror(all):
    interface(displayprecision = 4);
    _EnvUseHeavisideAsUnitStep := true;  
    Digits := 10;
    printf("Standard Packages Loaded\n");

The new default in Maple 2025 is to hide the Execution Group Boundaries in Worksheet mode.
In order to make them visible one has to use the menu

View > Show/Hide Contents > Execution Group Boundaries F9

or to press the F9 key.

The question: is there a method to have again visible boundaries by default? 

(Hiding the boundaries does not seem to be a good idea because an execution group can have (it is not clear why!) multiple prompts.)

"Error, (in dsolve/numeric/SC/firststep) unable to evaluate the partial derivatives of f(x,y) for stiff solution", I am trying to solve a system of PDEs in Maple, using discretisation schemes, but keep getting this error. Can anyone help me with this?

i did try and even replace the function w(t) by anotehr thing but is not working  how i can find that and make be answer of my pde?

k1.mw

a million time i try to figure out how i can get this plot ? why my graph  in countor is not same the 3D plot? where is problem?

Bgraph1.mw

Syntax for merging and overlaying all three graphs on a single plot.
Include three sets of iso-profit lines on the same axes:
– Case 1: thin solid lines
– case 2: brown dashed lines
– Case 3: grey semi-dashed lines
Also add vector arrows to show the direction of maximum profit increase.
Combined plot = Plot 1 + Plot 2 +  Plot 3
Attaching sheet:
case_1.mw                  case_2.mw                 Case_3.mw
 

sample graph: 

Is it possible to install and operate Maple toolbox 2025.2 with MATLAB R2025b on Linux (Ubuntu 24.04)  platform?

On Ubuntu 24.04 installation process hangs after location of Maple and Matlab folders at installer window.

Any idea what is wrong?

Of course, I know that actual Maple 2025 system requirements mention support only for MATLAB R2024b, but this is an obsolete version of MATLAB.

And finally, Is there any reliable and effective way how to switch between Maple and MATLAB symbolic engine?

When I use Maple to solve some complex polynomial system and trying different methods, for instance, using engine = traditional, it will sometimes lose or fail to find the solutions. In the document, it says Maple will convert to engine = groebner when it does not find solutions using traditional engine. As far as I know it is using resultant to eliminate variables, and the resultant is computed by pseudo remainder. The leading coefficient of the divisor is multiplied during each division to ensure that we include the case that it is zero.

But why this procedure will lose solutions sometimes? What makes Maple abandon this method?

It hangs are v(x) := for some reason.

NULL;

q := x -> v1*Dirac(x - a1) + v2*Dirac(x - a2) + v3*Dirac(x - a3);
NULL;

V := x -> -int(q(x), x = 0 .. x) + Ra + Rb*Dirac(x - L);
proc (x) options operator, arrow, function_assign; Units:-Simple\

  :-`+`(Units:-Simple:-`+`(Units:-Simple:-`-`(MTM:-int(q(x), x 

   = 0 .. x)), Ra), Units:-Simple:-`*`(Rb, Dirac(Units:-Simple:-\

  `+`(x, `-`(L))))) end proc

NULL;

M := x -> int(V(x), x = 0 .. x) + Ma + Mb*Dirac(x - L);
proc (x) options operator, arrow, function_assign; Units:-Simple\

  :-`+`(Units:-Simple:-`+`(MTM:-int(V(x), x = 0 .. x), Ma), 

   Units:-Simple:-`*`(Mb, Dirac(Units:-Simple:-`+`(x, 

   `-`(L))))) end proc

theta := x -> 1000000000000*(int(M(x), x = 0 .. x) + `θa` + `θb`*Dirac(x - L))/(E*S_mm);
proc (x) options operator, arrow, function_assign; Units:-Simple\

  :-`*`(Units:-Simple:-`+`(Units:-Simple:-`+`(MTM:-int(M(x), x 

   = 0 .. x), `θa`), Units:-Simple:-`*`(`θb`, 

   Dirac(Units:-Simple:-`+`(x, `-`(L))))), 1/(E*S_mm*10^(-12))) 

   end proc

v := x -> int(theta(x), x = 0 .. x);
proc (x) options operator, arrow, function_assign; MTM:-int(thet\

  a(x), x = 0 .. x) end proc

I get this message:

Why is it not working using the menu?

Why are characters printed with additional back ticks when decimal HTML code is used (see output (3) below). lprint((3)) does not print them.

Looks like an exception. Is there a reason for that? Can it be used for something?

Download back_ticks_with_decimal_code.mw

Good afternoon.

Here is (what appears to be) a simple assignment problem that involves scheduling 3 jobs through 2 machines, and I wish to minimize the total time required to complete all 3 jobs. Each job must be processed first on machine #1 before going to machine #2,and each machine can only handle one job at a time.

I have determined the optimal sequence to minimize the makespan (i.e., the completion time of the last job on machine #2) using a manual method and I was wondering if someone could review this (please see attached) and recommend a structured LP method or let me know if such a procedure exists in Maple's Optimization package.

Any help will be appreciated! 

Thanks for reading.

MaplePrimes_Nov_4.mw