Unanswered Questions

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

how to get the solution for this ode i am getting error 

in the pdf for the same parameter values getting plots but here it is showing error

santosh_sir_work.pdf

santosh_sir_work.mw

This is a report of a Maple_2015's bug, apparently fixed in more recent versions, but which may have persisted for a few versions beyond 2015.
I don't think it's necessary to fill out an RCS form.

All started with an error in my code which was balanced by a maple 2015 bug. So I didn't see any error until I sent my code to @C_R  who uses a newer Maple version.
More precisely, in my Maple 2015 code I defined a NxN matrix B, a vector A of length N, that I mistakenly defined as a vector column, and finally computed the quantity R = A . B . A+.
Of course Maple should have fire an error.

The bug is that Maple 2015 doesn't fire an error if A is a float vector and B a float matrix.

restart

kernelopts(version)

`Maple 2015.2, APPLE UNIVERSAL OSX, Dec 20 2015, Build ID 1097895`

(1)

A := Vector(2, symbol=a):
B := Matrix(2$2, symbol=b):
R := A.B.A^+

Error, (in LinearAlgebra:-Multiply) cannot multiply a column Vector and a Matrix

 

A := Vector(2, i -> i):
B := Matrix(2$2, (i, j) -> i+j):
R := A.B.A^+

Error, (in LinearAlgebra:-Multiply) cannot multiply a column Vector and a Matrix

 

A := evalf(Vector(2, i -> i)):
B := evalf(Matrix(2$2, (i, j) -> i+j)):
R := A.B.A^+

30.

(2)

R := A^+.B.A

30.

(3)
 

 

Download Maple_2015_Bug.mw

When clicking on a pink error message I get this

Can someone explain what is going on? Quite unusual for me all this.

I do not have a server to white list. What can I do about it?

Is that Sucuri thing safe?

Is there a way to disable / turn of ai in Maple Learn. The question is relevant because it is not allowed for our students to use AI during their exams.

Regards and happy holiday

using regular expression in Maple is little annoying, because one has to escape \ in the regx string itself, which makes it more complicated compared to other languages. For example

StringTools:-RegMatch("^\[.*\]$","[A]")

gives false. But

StringTools:-RegMatch("^\\[.*\\]$","[A]")

gives true.

Other languages have special function to generate the regx itself, which does not require escaping the \ when writing the regx Which makes it easier to see the regx (escaping is done under the cover). like this

Since all places and web sites that show examples of regx., do not have to escape \ before using, it will be good if Maple adds such special new function to StringTools to generate regx like the above so users do not have to remember to escape \.   

It is hard enough to use regx without having to also remember to escape things.

I could not find such a function in Maple. Does one exist?

Maple 2025.2

How to explain this strange behavior?   odetest(sol,ode) does not give zero. But odetest(sol,[ode,IC]) gives [0,0]

Same solution and same ode. Why adding IC, now odetest says solution verifies the ode, but without adding IC, it does not give zero right away. I know I can simplify the result to zero. But the point is that it should have given zero right away, because that is what it did when adding IC.

Should it not have given zero in first case also?

Can't upload worksheet due to security. Here is code and screen shot

ode := diff(y(x),x) + cos(1/exp(2*x))*y(x) = sin(1/exp(x));
IC := a*D(y)(x0)+c*y(x0) = b*y0;
sol:=y(x) = ((-cos(exp(-2*x0))*a + c)*Int(sin(exp(-tau))*exp(-1/2*Ci(exp(-2*tau))), tau = 0 .. x0) + Int(sin(exp(-tau))*exp(-1/2*Ci(exp(-2*tau))), tau = 0 .. x)*(cos(exp(-2*x0))*a - c) + exp(-1/2*Ci(exp(-2*x0)))*(a*sin(exp(-x0)) - b*y0))*exp(1/2*Ci(exp(-2*x)))/(cos(exp(-2*x0))*a - c);

odetest(sol,ode);

#not zero

#now

odetest(sol,[ode,IC]);

#gives [0,0]

 

Variation of (a) Skin friction ∂W/∂Z​, (b) Heat Transfer ∂θ/∂Z​, and (c) Mass Transfer ∂ϕ/∂Z​ for γ=10.0, Pr=7.0, ε=1.0, Nt=0.4, and Nb=0.2.

10.0   0.03301 1.90406 0.21772
20.0   0.01212 1.90403 0.20269
30.0   0.00727 1.90402 0.19325
40.0   0.00522 1.90400 0.18645


how to get this values by solving the PDE by using the pdsolve method 

Variation of (a)W(b) θ and (c) ϕ for different value of γ when ε = 10.0, Nb = 0.4, ε = 10.0, Sc = 0.5 and Pr = 7.0.
consider X as 0.1

plume_work.mw

Why one is no longer able to upload worksheet here showing a problem? I found an internal error in int() but can't upload worksheet.

When I click on the green arrow and select my worksheet, I get this message

What is going on? I am on windows 10 and I tried 2 different browsers. So the problem is on the Mapleprimes site.

Can anyone else try to upload a worksheet to test to see if they get same problem?

I frequently receive this message after installing the most recent Maple update:

Can anyone help me with this? Thank you so much for your valuable support.

Hello,

I have upgraded to maple 2025, but the ui fonts are too small and very thin. I went to Files -> Options -> Interface -> Default Zoom, thet sat it up to 150%. It only changed the document area not the UI options. This solution used to work with Maple 2024. I am on ubuntu 22.04.

DO not know if this is new in Maple 2025.2 or not as I have not looked yet if it is possible to install Maple 2025.1 on my new PC given Maple 2025.2 is already installed.

Found That Maple 2025.2 gives "Error, (in dsolve) numeric exception: division by zero" when asked to solve this ode using Lie symmetry.  The error comes when it tried to 

                        Computing canonical coordinates for the symmetry 

Even if this problem was in earlier Maple versions, this ofcourse should not happen.

interface(version);

`Standard Worksheet Interface, Maple 2025.2, Windows 10, November 11 2025 Build ID 1971053`

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1882 and is the same as the version installed in this computer, created 2025, December 1, 6:58 hours Pacific Time.`

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 29 and is the same as the version installed in this computer, created June 23, 2025, 10:25 hours Eastern Time.`

libname;

"C:\Users\me\maple\toolbox\2025\Physics Updates\lib", "C:\Users\me\maple\toolbox\2025\Maple Customer Support Updates\lib", "C:\Program Files\Maple 2025\lib"

restart;

ode:=sin(x)*diff(y(x), x, x) + (2*sin(x) - cos(x))*diff(y(x), x) + (sin(x) - cos(x))*y(x) = exp(-x);

sin(x)*(diff(diff(y(x), x), x))+(2*sin(x)-cos(x))*(diff(y(x), x))+(sin(x)-cos(x))*y(x) = exp(-x)

dsolve(ode)

y(x) = exp(arcsin(cos(x)))*c__2+exp(arcsin(cos(x)))*cos(x)*c__1+exp(arcsin(cos(x)))*(-(Int(csc(x)^2*exp(-arcsin(cos(x))-x), x))*cos(x)+Int(cot(x)*csc(x)*exp(-arcsin(cos(x))-x), x))

dsolve(ode,Lie)

Error, (in dsolve) numeric exception: division by zero

 

 

Download division_by_zero_dsolve_maple_2025_2_on_dec_2_2025.mw

I've seen many here recommend using the screen reader for Maple 2025. So this is first time I tried it.

Clicked on this second icon in my windows 10 start menu

Maple came up using the old UI, which is good:

But here comes the big problem. The file->Open menu does not work. It automatically opened in location which is not what I want. I wanted to navigate to different place on my PC. But anything I click on just generates loud beep and does nothing. Can't type anything to change location either.

So can't open any file. Not only that, It is stuck and can't even close the windows. Can't get out. Everything is stuck. 

It could be because I have 2 monitors. I had this open on the second monitor on the right. Everything on the second monitor now do not respond like Maple. Luckily, on the left monitor I was able to start task manager and kill Maple in order to get out of this hang.    

Basically screen reader does not work at all for me. If I can't open a file.

It could be due to using 2 monitors. I do not know.

Does file open work for others?

Here is small movie.

Do not know if this is new or not.

I have found about 12 Maple crashes so far in just 2 days running a test in Maple 2025.2

But this one I am not sure if it is new or not as never seen it before.

Could someone please just run this in Maple 2025.1 and see if you get same crash? So I know if it is new or not. Only have Maple 2025.2 on this new PC.

Calling solve causes Maple server to crash. Save your work before just in case.

restart;

interface(version);

`Standard Worksheet Interface, Maple 2025.2, Windows 10, November 11 2025 Build ID 1971053`

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1881 and is the same as the version installed in this computer, created 2025, October 7, 16:4 hours Pacific Time.`

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 29 and is the same as the version installed in this computer, created June 23, 2025, 10:25 hours Eastern Time.`

sol:=ln( (y-1)^(1/3)* (y^2+y+1)^(1/3) ) - ln(y) = 2/5* ln(t^2+1)+_C1;

ln((y-1)^(1/3)*(y^2+y+1)^(1/3))-ln(y) = (2/5)*ln(t^2+1)+_C1

infolevel[solve]:=5;

5

solve( sol,y);

Main: Entering solver with 1 equation in 1 variable

Dispatch: dispatching to Radicals handler

Transformer:   solving for linear equation in y

Recurse: recursively solving 1 equations and 4 inequations in 1 variables

Dispatch: dispatching to ln handler (extension)

Dispatch: logarithm substitution _S000002 = ln(_S000001)

Recurse: recursively solving 1 equations and 4 inequations in 1 variables

Dispatch: dispatching to ln handler (extension)

Dispatch: logarithm substitution _S000003 = ln(t^2+1)

Transformer:   solving for linear equation in _S000003

Recurse: recursively solving 1 equations and 3 inequations in 1 variables

Dispatch: dispatching to ln handler (extension)

Dispatch: logarithm substitution _S000004 = ln(exp(_S000002)^3+1)

Recurse: recursively solving 2 equations and 3 inequations in 2 variables

Dispatch: dispatching to ln handler (extension)

Dispatch: logarithm substitution _S000005 = ln(exp(_S000002)^6+3*exp(_S000002)^3+3)

Recurse: recursively solving 3 equations and 3 inequations in 3 variables

Dispatch: dispatching to Exponentials handler

Transformer:   solving for linear equation in _S000005

Recurse: recursively solving 3 equations and 4 inequations in 4 variables

Dispatch: dispatching to Exponentials handler

Transformer:   solving for linear equation in _S000004

Recurse: recursively solving 3 equations and 5 inequations in 5 variables

Dispatch: dispatching to Exponentials handler

Transformer:   solving for linear equation in _S000002

Recurse: recursively solving 3 equations and 6 inequations in 6 variables

Dispatch: dispatching to Rename handler

Dispatch: renaming exp(5/2*_C1) = _S000012, exp(-5/2*_C1) = 1/_S000012

Recurse: recursively solving 3 equations and 6 inequations in 6 variables

Dispatch: handling polynomials of the form a*x^n-b

Dispatch: dispatching to PolynomialSystem handler

Main: polynomial system split into 1 parts under preprocessing

Main: using RegularChains based methods

SolverVariableOrder: using the variable order  _S000008 > _S000006 > _S000010

TriangularDecomposition: using deterministic algorithm for decomposition

Download calling_solve_crashes_maple_2025_2_nov_28_2025.mw

Note that this crash happens even when removing Physics update and SupportTools from libname.

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

interface(version);

`Standard Worksheet Interface, Maple 2025.2, Windows 10, November 11 2025 Build ID 1971053`

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 29 and is the same as the version installed in this computer, created June 23, 2025, 10:25 hours Eastern Time.`

Physics:-Version();

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

restart;

Original result. No problem

 

print(`convert/diff`);

proc (a, { useeval::truefalse := false }) local ee, zD; ee := `PDEtools/usediff`(a); zD := indets(ee, 'And(function, satisfies(proc (f) options operator, arrow; (op(0, f))::`PDEtools/D/structure` end proc))'); if zD = {} then ee else _Env_t_in_use := `tools/get_symbols`(a); if useeval then zD := map(`convert/diff/D_to_eval@diff`, zD, ':-useEval'); zD := map(proc (u) options operator, arrow; lhs(u) = subsop(0 = eval, rhs(u)) end proc, zD); subs(zD, ee) else subs(map(`convert/diff/D_to_eval@diff`, zD), a) end if end if end proc

T:=D(x)(infinity):

PDEtools:-difforder(convert(T,diff))

1

 

 

 

After call Physics:-Setup

 

restart;

Physics:-Setup('assumingusesAssume' = false):

print(`convert/diff`);

proc () local ans; ans := usepdiff(args); if has([ans], 'D') then ans := Physics:-OriginalValue["convert/diff"](ans, args[2 .. -1]) end if; ans end proc

T:=D(x)(infinity):

PDEtools:-difforder(convert(T,diff))

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

 

 

 

 

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?


 

interface(version);

`Standard Worksheet Interface, Maple 2025.2, Windows 10, November 11 2025 Build ID 1971053`

Physics:-Version();

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

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 29 and is the same as the version installed in this computer, created June 23, 2025, 10:25 hours Eastern Time.`

restart;

eq:=D(y)(0)+1 = 0;
solve(eq,D(y)(0));

(D(y))(0)+1 = 0

-1

PDEtools:-Solve(eq,D(y)(0));

Error, (in PDEtools:-Solve) required an indication of the solving variables for the given system

 


 

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

interface(version);

`Standard Worksheet Interface, Maple 2025.2, Windows 10, November 11 2025 Build ID 1971053`

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 29 and is the same as the version installed in this computer, created June 23, 2025, 10:25 hours Eastern Time.`

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1881 and is the same as the version installed in this computer, created 2025, October 7, 16:4 hours Pacific Time.`

restart;

Original result. No problem

 

print(`convert/diff`);

proc (a, { useeval::truefalse := false }) local ee, zD; ee := `PDEtools/usediff`(a); zD := indets(ee, 'And(function, satisfies(proc (f) options operator, arrow; (op(0, f))::`PDEtools/D/structure` end proc))'); if zD = {} then ee else _Env_t_in_use := `tools/get_symbols`(a); if useeval then zD := map(`convert/diff/D_to_eval@diff`, zD, ':-useEval'); zD := map(proc (u) options operator, arrow; lhs(u) = subsop(0 = eval, rhs(u)) end proc, zD); subs(zD, ee) else subs(map(`convert/diff/D_to_eval@diff`, zD), a) end if end if end proc

T:=D(x)(infinity):

PDEtools:-difforder(convert(T,diff))

1

 

 

 

After call Physics:-Setup. now works OK since Physics update is installed

 

restart;

Physics:-Setup('assumingusesAssume' = false):

print(`convert/diff`);

proc () local ans; ans := usepdiff(args); if has([ans], 'D') then ans := Physics:-OriginalValue["convert/diff"](ans, args[2 .. -1]) end if; ans end proc

T:=D(x)(infinity):

PDEtools:-difforder(convert(T,diff))

1

 

 

 

Download why_code_changes_calling_Physics_maple_2025_2_nov_24_2025_V2.mw

 

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