Hi there.

There is an issue with following limits in Maple 2025:

Maple returned an incorrect zero answers. Plotting functions we see that non-zero limits do exist:

Thank you.

limits.mw

Another very serious bug in Maple.

I have code that simplifies intitial conditions passed.

I found that simplify((D@@2)(y)(Pi) = 0) gives error 

Error, (in unknown) invalid input: diff received Pi, which is not valid for its 2nd argument

but Pi is constant. It works for any other values other than Pi.

This only happens when adding Physics:-Setup(assumingusesAssume = true):

Any idea why this happens?

Download simplify_fail_when_adding_physics_sept_27_2025.mw

I am interested in determining the density function which results from multiplying two random variables.  I have read about the Mellin Transformation, but I just end up confused.  I have two random variables:  f[1], which is nonzero on the 0 < t < 2 interval, and f[2], which is nonzero on the 0 < t < 1 interval.  Of course, both of these random variables sum to one when evaluated.

Any thoughts on how I can obtain the density function for this?  My work is below.

Download Inquiry.mw

...but it's easily solvable with the help of a trick. My main concern is the path to the solution for the attached Diophantine equation. I was able to solve the problem both with pen and paper and then in Maple. There's certainly a more elegant way. I'm particularly interested in a special Maple command. However, I don't want to ask for it here yet, as it would give a hint of the trick and spoil the fun of solving the puzzle.

Download Diophant.mw

Maple 2025.1 on Linux.

I am not able to make MWE after 2 days trying. But this crash happens each time when I run my main application at same place.

So it is related to memory. Since in small example, it does not happen.

Sometimes I get server crash and sometimes I get message  I never seen before  invalid nesting of _Inert_HASH structure and it always happens on the call to the second line in `assuming/restore_previous_state`; shown below.  The crash says stack limit reached.

I have 92 GB RAM.

it happens on the command 

I could only for now make a small movie. with few debug commands I did.

If someone can suggest what other debug commands I could do to help find why this happen, I will try them. Maybe look at stack or examine some other maple internal data.

Here is the movie (you can put the mouse on the image and right click->open in new tab. To make it larger and easier to see)

It happen when I have odetest inside try/catch. And in the catch, call `assuming/restore_previous_state`;

Again, I am not able to make MWE, but I can reproduce this each time by running my main application.

It clear this is a bug in Maple internal in `assuming/restore_previous_state`; which was added not long ago in SupportTools. See https://www.mapleprimes.com/questions/240459-Why-Assuming-Keeps-Assumptions-On-Variables#answer309898  for reference.

Calling `assuming/restore_previous_state` is to clear stuck assumptions that Maple had when using odetest with assumption that were not being cleared correctly. But it seems there is a problem in the implementation of this function.

in here i want the system which when i found the system it contain a singularity but by some changing of system we can remove it, i know how he did that but i can't do it by coding, also after removing which i did by hand , there is another problem which equalibruiom points is to long how i can make it be shorter becuase contain two function i don't know how do that can i change the coiefecient of any function by another letter? also for phase portrait i need `conserved quantity` which last code is not work for finding this kind of system ? and how decide about jacobian if the `conserved quantity` is know by that after determine the points it will be clear on plots, i write the code untill finding the `conserved quantity` becuase code not run i didn't find jacobian and phase portrait but i will put the code of jacobian and phase portrait too! 

bi-1.mw

Even though I missed the reference to "algebraic number of type a+b*sqrt(13)" in the solutions to the previous problem, here's another puzzle from school:
Let p and q be prime numbers. Show that there are infinitely many prime numbers such that p^2 - q^2 is divisible by 24.

Easy way to solve 3 equation simultaneously?:

Download Q_solve.mw

Determine all pairs of positive integers (x;y) such that: sqrt(x) + sqrt(y) = sqrt(637)

I would like to keep writing commands on the same line without automatically creating a new line break. Is there a way to achieve this in Maple?

In here i replaced but i don't know why still the D[1](f)(x, y, 0, t) is remain in my function in equation eqt1, beside this my function contain imaginary part we can plot this or we have to remove that somehow?

eval.mw

How to solve this equation to get the the similar plots given in pdf peristatic_flow_work.pdf

here is the work sheet for the problem which is given in the pdf 

Download pulatile_flow_error.mw

I want to change the datatype of a column of a Dataframe imported from Excel.

The import succeeds, and I can change the data type of numeric columns (from the default 'anything' to, say, float).

But conversion fails for all string columns. For example:

DataNew := SubsDatatype(Data, "UN Region", string);

throws the following error:

Error, (in DataSeries:-SubsDatatype) in datatype conversion; try using the 'conversion' option for data type string

The column in question has values such as "Southern Asia", which I would have thought would convert.

What am I doing wrong?

Groupings([a, b, ..., n], k)

Is there a built-in function in Maple that generates all possible groupings of the elements [a, b, ..., n] taken k at a time?

Example:

Groupings([a,b,c,d], 2)

Expected output:

[[[[a, b], c], d], [a, [[b, c], d]], [[a, [b, c]], d], [a, [b, [c, d]]], [[a, b], [c, d]]]

B12 := -6*(p1 + p2)/(p1 - p2)^2;
F2 := (theta1*theta2*p1^2 + (-2*p2*theta1*theta2 - 6)*p1 + theta1*theta2*p2^2 - 6*p2)/(p1 - p2)^2;

to..

F2 := theta1*theta2 + (-6*p1 - 6*p2)/(p1 - p2)^2
F2:= theta1*theta2 + B12  ( how to get this ?)

Should be very easy, but it is not