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Question: Result of odetest changes depending on previous command used.

Question:Result of odetest changes depending on previous command used.

nm 10793 Maple 2024
differential-equations odetest
June 06 2024
2

If I do    odetest(...,odeA) I get correct result. But if I do    odetest(...,odeB);  odetest(...,odeA);   now it gives wrong output for the odeA one. 

Same exact code. It just depends on the call done before it.

Why would issuing a command before changes the output of odetest? It seems Maple remembers something from last call. But I have no idea how to fix this.

Is there a way to tell odetest not to remember or cache any results from last calls? i.e. Can I clear its remember table before calling odetest??

This is messing all my testing now since I get different result each time depending on which call was made before. I can't do restart before testing each ode, since this is done in a loop.  I just need a way to tell Maple to clear its internal cache so that each call to odetest is not affected by last call result. 

Doing forget(odetest); before the call had no effect.

Reported to Maplesoft.

Worksheet below

``

> 

interface(version);

`Standard Worksheet Interface, Maple 2024.0, Windows 10, March 01 2024 Build ID 1794891`

> 

restart;

4556

> 

#EXAMPLE 1
ode:=x*diff(y(x),x)^n=0;
sol:=dsolve(ode);
odetest(sol,ode);

x*(diff(y(x), x))^n = 0

y(x) = c__1

0

> 

restart;

4556

> 

ode:=diff(y(x),x)^n=0;
sol:=dsolve(ode);
odetest(sol,ode);

(diff(y(x), x))^n = 0

y(x) = c__1

0^n

> 

##EXAMPLE 1 repeated. Why now different result??

ode:=x*diff(y(x),x)^n=0;
sol:=dsolve(ode);
odetest(sol,ode);

x*(diff(y(x), x))^n = 0

y(x) = c__1

x*0^n

Download why_different_result_from_odetest_june_6_2024.mw

Update

FYI, I got email from Maplesupport that Maple R&D group will look at this issue.

So hopefully this will be fixed in a future version of Maple.  

I am not able to find a workaround but doing tracing I see that odetest does rememebr something from last call but have no idea to fix this myself.
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