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possible new bug in V 22 of SupportTools...

nm 11643 Maple 2025
ode differential-equations odetest
June 02 2025
1 7

After updating to V 22 of supportTools, I found a new error.

This works sheet using V 22 gives this

> 

interface(version);

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

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1873 and is the same as the version installed in this computer, created 2025, May 18, 21:44 hours Pacific Time.`

> 

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 22 and is the same as the version installed in this computer, created May 28, 2025, 23:36 hours Eastern Time.`

> 

restart;
> 

IC:=y(2) = 2;
ode:=diff(y(x),x) = (x-y(x))^(1/2);
sol:=y(x) = -(LambertW(-exp(-1/2*x))+1)^2+x;

y(2) = 2

diff(y(x), x) = (x-y(x))^(1/2)

y(x) = -(LambertW(-exp(-(1/2)*x))+1)^2+x

> 

odetest(sol,ode) assuming positive;

Error, (in property/AndProp/+) too many levels of recursion

> 

odetest(sol,[ode,IC]) assuming positive;

Error, (in AndProp:-UseCache) too many levels of recursion

 

 

Download bug_in_odetest_with_lambertW_june_2_2025.mw

But same code works OK in V 21

> 

interface(version);

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

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1873 and is the same as the version installed in this computer, created 2025, May 18, 21:44 hours Pacific Time.`

> 

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 22. The version installed in this computer is 21 created May 28, 2025, 23:36 hours Eastern Time, found in the directory /home/me/maple/toolbox/2025/Maple Customer Support Updates/lib/Maple`

> 

IC:=y(2) = 2;
ode:=diff(y(x),x) = (x-y(x))^(1/2);
sol:=y(x) = -(LambertW(-exp(-1/2*x))+1)^2+x;

y(2) = 2

diff(y(x), x) = (x-y(x))^(1/2)

y(x) = -(LambertW(-exp(-(1/2)*x))+1)^2+x

> 

odetest(sol,ode) assuming positive;

-csgn(LambertW(-exp(-(1/2)*x))+1)*LambertW(-exp(-(1/2)*x))-csgn(LambertW(-exp(-(1/2)*x))+1)+LambertW(-exp(-(1/2)*x))+1

> 

odetest(sol,[ode,IC]) assuming positive;

[-csgn(LambertW(-exp(-(1/2)*x))+1)*LambertW(-exp(-(1/2)*x))-csgn(LambertW(-exp(-(1/2)*x))+1)+LambertW(-exp(-(1/2)*x))+1, 0]

 

 

Download no_bug_in_odetest_with_lambertW_june_2_2025.mw

why now need to restart all of Maple to ...

nm 11643 Maple 2025
restart supporttools
June 02 2025
2 0

This is not a big deal, but I was wondering why it changed. Before, after doing SupportTools:-Version(latest); to get latest version, the message used to say to just do restart; to use the new version of SupportTools (i,e. no need to close all of Maple). (I remember this, but I have no screen shot now to show this old message). I always used to just do restart; and it always worked.

Now, with version 22, the message changed, it now says to close and restart all of Maple

Why this change happened?  

Maple 2025 on Linux

How to odetest ode solution when using L...

nm 11643 Maple 2025
ode dsolve differential-equations
May 29 2025
1 0

For some reason, I get dozens of ode's that fail to odetest when using method='laplace' with dsolve.

Yet, all the solutions are correct. These are from textbooks.

I tried giving odetest assumptions but nothing worked so far. So I am thinking of just ignoring result of odetest when laplace method is used and to assume it is correct each time. Otherwise, I will get false negative all the time on these.

Thought to ask if someone knows why this happens and if there is some universal trick to use when calling odetest on such solutions.

Here is worksheet with few examples where odetest do not verify the solutions (even though they are "correct", when solving these ode's by hand). 

May be if odetest was told that the solution was generated using method='laplace' it will help it, but there is no such option (as in the case with 'series' option). 

Btw, if method='laplace' is not used on these examples, then odetest have no problem verifying the solutions and gives zero on all of them.

> 

interface(version);

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

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1873 and is the same as the version installed in this computer, created 2025, May 18, 21:44 hours Pacific Time.`

> 

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 21 and is the same as the version installed in this computer, created May 28, 2025, 23:36 hours Eastern Time.`

> 

restart;
> 

ode:=diff(x(t),t$2)+4*diff(x(t),t)+13*x(t) = f(t):
ic:=x(0) = 0, D(x)(0) = 0:
sol:=dsolve([ode,ic],x(t),method='laplace');
odetest(sol,[ode,ic]);

x(t) = (1/3)*(int(f(_U1)*exp(-2*t+2*_U1)*sin(3*t-3*_U1), _U1 = 0 .. t))

[-(1/6)*(-(26*I)*(Int(f(_U1)*sinh(-(3*I)*t+(3*I)*_U1)*exp(2*_U1+(3*I)*t), _U1 = 0 .. t))-(13*I)*exp((6*I)*t)*(Int(exp((2-3*I)*_U1)*f(_U1), _U1 = 0 .. t))+(13*I)*(Int(exp((2-3*I)*_U1)*f(_U1)*exp((6*I)*_U1), _U1 = 0 .. t)))*exp((-2-3*I)*t), 0, 0]

> 

ode:=diff(diff(x(t),t),t)+4*x(t) = Dirac(t)+Dirac(t-Pi):
ic:=x(0) = 0, D(x)(0) = 0:
sol:=dsolve([ode,ic],x(t),method='laplace');

odetest(sol,[ode,ic]);

x(t) = (1/2)*sin(2*t)*(1+Heaviside(t-Pi))

[-Dirac(t), 0, -1]

> 

ode:=diff(diff(x(t),t),t)+4*x(t) = Dirac(t):
ic:=x(0) = 0, D(x)(0) = 0:
sol:=dsolve([ode,ic],x(t),method='laplace'):
odetest(sol,[ode,ic]);

[-Dirac(t), 0, -1]

> 

ode:=diff(diff(x(t),t),t)+4*diff(x(t),t)+8*x(t) = f(t):
ic:=x(0) = 0, D(x)(0) = 0:
sol:=dsolve([ode,ic],x(t),method='laplace'):
odetest(sol,[ode,ic]);

[-2*(-(2*I)*(Int(f(_U1)*sinh((2*I)*_U1-(2*I)*t)*exp(2*_U1+(2*I)*t), _U1 = 0 .. t))+2*(Int(f(_U1)*cosh((2*I)*_U1-(2*I)*t)*exp(2*_U1+(2*I)*t), _U1 = 0 .. t))+I*(Int(exp((2-2*I)*_U1)*exp((4*I)*_U1)*f(_U1), _U1 = 0 .. t))-I*exp((4*I)*t)*(Int(exp((2-2*I)*_U1)*f(_U1), _U1 = 0 .. t))-(Int(exp((2-2*I)*_U1)*exp((4*I)*_U1)*f(_U1), _U1 = 0 .. t))-exp((4*I)*t)*(Int(exp((2-2*I)*_U1)*f(_U1), _U1 = 0 .. t)))*exp((-2-2*I)*t), 0, 0]

> 

 


 

Download how_to_odetest_laplace_solution_may_29_2025.mw

 

solve failing on second time called....

nm 11643 Maple 2025
solve assuming physics
May 28 2025
0 4

I've been debugging this for 20 hrs and finally able to make an example.

I noticed that solve() suddenly no longer works and times out.

First time calling solve() works. Second time it I see message

               Warning, solve may be ignoring assumptions on the input variables.

And it hangs.  Same exact code.   It has to do with calling odetest before and using Physics:-Setup('assumingusesAssume' = false):

i.e. this works
  
     odetest(...) assuming integer
     solve(....) #no hang
     odetest(....) assuming positive

     odetest(...)  assuming integer
     solve(....)  #no hang

But this does not work

     odetest(...) assuming integer
     solve(....) #no hang
     Physics:-Setup('assumingusesAssume' = false):
     odetest(....) assuming positive
     Physics:-Setup('assumingusesAssume' = true):
     odetest(...) assuming integer
     solve(...)   #HANGS     

Here is worksheet showing the problem. If I remove first call to odetest, solve do not hang.

Also removing Physics:-Setup('assumingusesAssume' = false):, solve also works OK. (ie. does not hang)

So it has to do with some internal caching which causes solve to stop working.

Can others reproduce this and can cause it and how to fix it so solve do not hang second time?

The input used below is not important. It is just what I found to cause this. One would expect solve() to work same way for same input all the time.

Also, same problem happens when using PDEtools:-Solve instead of solve. It hangs second time.

> 

interface(version);

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

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1873 and is the same as the version installed in this computer, created 2025, May 18, 21:44 hours Pacific Time.`

> 

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 20 and is the same as the version installed in this computer, created May 23, 2025, 23:34 hours Eastern Time.`

> 

restart

DEFINE input

 
> 

ode:=y(x)*sqrt(1 + diff(y(x), x)^2) - a*y(x)*diff(y(x), x) - a*x = 0:
sol:=-_C4^2 + (-y(x)*sqrt(_C4^2/y(x)^2) + a*x)^2/a^2 + y(x)^2 = 0:
ode_to_test:=y(x)*(1+diff(y(x),x)^2)^(1/2)-a*y(x)*diff(y(x),x)-a*x = 0:

FIRST TIME solve works

 
> 

    try
        timelimit(30,(odetest(sol,ode,y(x)) assuming integer));
    catch:
        NULL;
    end try:

    try
        timelimit(30,[solve(ode_to_test,diff(y(x),x))]);
        print("SOLVE worked");              
    catch:
        print("WHY TIMED OUT??");              
    end try:

    Physics:-Setup('assumingusesAssume' = false):
    try
        timelimit(30, (odetest(sol,ode,y(x)) assuming positive) );
    catch:
        NULL;
    end try:
    Physics:-Setup('assumingusesAssume' = true):

"SOLVE worked"

> 

 

> 

 

RUN SAME CODE AS ABOVE again, now it does not work

 
> 

    try
        timelimit(30,(odetest(sol,ode,y(x)) assuming integer));
    catch:
        NULL;
    end try:

    try
        timelimit(30,[solve(ode_to_test,diff(y(x),x))]);
        print("SOLVE worked");              
    catch:
        print("WHY TIMED OUT??");              
    end try:

    Physics:-Setup('assumingusesAssume' = false):
    try
        timelimit(30, (odetest(sol,ode,y(x)) assuming positive) );
    catch:
        NULL;
    end try:
    Physics:-Setup('assumingusesAssume' = true):

Warning, solve may be ignoring assumptions on the input variables.

"WHY TIMED OUT??"

 

 

 

 

Download why_solve_stops_working_maple_2025_may_28_2025.mw

This worksheet below shows that by removing Physics:-Setup('assumingusesAssume' = false): now solve works OK second time. (I turn on/off Physics:-Setup('assumingusesAssume' since I found sometimes it can help with odetest to turn it off in some other cases. But now I am scared of touching this setting as it seems to have side effects internally)

> 

interface(version);

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

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1873 and is the same as the version installed in this computer, created 2025, May 18, 21:44 hours Pacific Time.`

> 

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 20 and is the same as the version installed in this computer, created May 23, 2025, 23:34 hours Eastern Time.`

> 

restart

DEFINE input

 
> 

ode:=y(x)*sqrt(1 + diff(y(x), x)^2) - a*y(x)*diff(y(x), x) - a*x = 0:
sol:=-_C4^2 + (-y(x)*sqrt(_C4^2/y(x)^2) + a*x)^2/a^2 + y(x)^2 = 0:
ode_to_test:=y(x)*(1+diff(y(x),x)^2)^(1/2)-a*y(x)*diff(y(x),x)-a*x = 0:

FIRST TIME solve works

 
> 

    try
        timelimit(30,(odetest(sol,ode,y(x)) assuming integer));
    catch:
        NULL;
    end try:

    try
        timelimit(30,[solve(ode_to_test,diff(y(x),x))]);
        print("SOLVE worked");              
    catch:
        print("WHY TIMED OUT??");              
    end try:

    try
        timelimit(30, (odetest(sol,ode,y(x)) assuming positive) );
    catch:
        NULL;
    end try:

"SOLVE worked"

> 

 

> 

 

RUN SAME CODE AS ABOVE again, now it does not work

 
> 

    try
        timelimit(30,(odetest(sol,ode,y(x)) assuming integer));
    catch:
        NULL;
    end try:

    try
        timelimit(30,[solve(ode_to_test,diff(y(x),x))]);
        print("SOLVE worked");              
    catch:
        print("WHY TIMED OUT??");              
    end try:

    try
        timelimit(30, (odetest(sol,ode,y(x)) assuming positive) );
    catch:
        NULL;
    end try:

"SOLVE worked"

 

 

 

 

Download why_solve_stops_working_maple_2025_may_28_2025_V2.mw

should solve(x^n=0,x) give zero?...

nm 11643 Maple 2025
solve
May 25 2025
1 1

Should maple have given solution to x as zero in the following?

solve(x^n=0,x)

What if n is zero? what if n is negative?  

Another program I tried this on gives

Maple 2025

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