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division by zero calling dsolve with Abe...

nm 10973 Maple 2025
ode dsolve differential-equations
Yesterday at 8:38 PM
1 2

Do you think could be a bug in dsolve? 

> 

restart;
> 

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 1861 and is the same as the version installed in this computer, created 2025, April 10, 15:58 hours Pacific Time.`

> 

restart;
> 

ode:=x^2+3*x*diff(y(x),x)=y(x)^3+2*y(x);
DEtools:-odeadvisor(ode);
dsolve([ode,y(1)=1],[Abel])

x^2+3*x*(diff(y(x), x)) = y(x)^3+2*y(x)

[_rational, _Abel]

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

 

 

Download dsolve_division_by_zero_abel_april_16_2025.mw

If I do not tell it to use Abel, then dsolve does not give divison by zero.

Maple 2025 on Linux

where is Maple's help page for Abel ...

nm 10973 Maple 2025
ode differential-equations documentation
Yesterday at 10:22 PM
0 1

I can't find the help page for Abel second kind, class B. 

Maple has help page for Abel second kind, class A and Abel second kind, class C. But not for class B. 

Here is an example of Abel second kind class B

ode:=(3*t*y(t)+y(t)^2)+(t^2+t*y(t))*diff(y(t),t)=0;
DEtools:-odeadvisor(ode)

I wanted to know the difference and the transformation used for class B to make it Abel first kind.

I googled and can't find it. Also local help skips over class B.

Is this documented somewhere else?

btw, find error on the help page for class A. Transformation used is wrong. Will leave this for another question.

workaround for Maple unable to verify it...

nm 10973 Maple 2025
ode dsolve series
April 13 2025
2 6

I've reported this problem to Maple many years ago but still not fixed in Maple 2025.

Maple not able to verify its own solution on some series solutions using odetest.

Any one can suggest a workaround one can use other than odetest to verify ode solution when using series? Or have an idea why this happens?

The solution is correct but for some reason odetest returns FAIL 

Below is one example of many I have

> 

restart;
> 

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 1861 and is the same as the version installed in this computer, created 2025, April 10, 15:58 hours Pacific Time.`

> 

ode:=x*diff(y(x),x$2)+y(x)=0;
IC:=y(0)=1;
maple_sol:=dsolve([ode,IC],y(x),'series');
odetest(maple_sol,[ode,IC],'series','point'=0);

x*(diff(diff(y(x), x), x))+y(x) = 0

y(0) = 1

y(x) = c__1*x*(series(1-(1/2)*x+(1/12)*x^2-(1/144)*x^3+(1/2880)*x^4-(1/86400)*x^5+O(x^6),x,6))+ln(x)*(series(-x+(1/2)*x^2-(1/12)*x^3+(1/144)*x^4-(1/2880)*x^5+O(x^6),x,6))+(series(1-(3/4)*x^2+(7/36)*x^3-(35/1728)*x^4+(101/86400)*x^5+O(x^6),x,6))

Warning, unable to compute series necessary to test the given solution

FAIL

 

 

Download series_unable_to_odetest_april_12_2025.mw

which method to use to remove RootOf ?...

nm 10973 Maple 2025
rootof
April 07 2025
1 0

I know of 3 ways to remove RootOf, but sometimes they give different result. How does one decide which to use? This is done in code. So method to decide can't depend on looking at the screen and see which result one "likes" more than the other.

Is allvalues() the one to use all the time? Could one of these 3 methods fail, and then one has to try the next one?

> 

 

> 

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 1859 and is the same as the version installed in this computer, created 2025, April 6, 14:34 hours Pacific Time.`

> 

restart
> 

e:=y*4^(1/3)*((4*x^2*RootOf(_Z^2*y - 4*_Z*x + y) - y^2*RootOf(_Z^2*y - 4*_Z*x + y) - x*y)/y^2)^(1/3) - _C2;

y*4^(1/3)*((4*x^2*RootOf(_Z^2*y-4*_Z*x+y)-y^2*RootOf(_Z^2*y-4*_Z*x+y)-x*y)/y^2)^(1/3)-_C2

> 

convert(e,radical)

y*4^(1/3)*((4*x^2*(2*x+(4*x^2-y^2)^(1/2))/y-y*(2*x+(4*x^2-y^2)^(1/2))-x*y)/y^2)^(1/3)-_C2

> 

DEtools:-remove_RootOf(e)

(1/16)*(c__2^3+4*x*y^2)^2/(y*(4*x^2-y^2)^2)-(c__2^3+4*x*y^2)*x/(y*(4*x^2-y^2))+y = 0

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allvalues( e)

y*4^(1/3)*((4*x^2*(2*x+(4*x^2-y^2)^(1/2))/y-y*(2*x+(4*x^2-y^2)^(1/2))-x*y)/y^2)^(1/3)-c__2, y*4^(1/3)*((-4*x^2*(-2*x+(4*x^2-y^2)^(1/2))/y+y*(-2*x+(4*x^2-y^2)^(1/2))-x*y)/y^2)^(1/3)-c__2


 

Download removing_rootof_april_7_2025.mw

How to create a section in Maple 2025 UI...

nm 10973 Maple 2025
ribbon section user-interface
March 28 2025
2 0

How does one create a new section using UI in Maple 2025?

I've done this many times in Maple 2024. To make section there, I simply do
   Insert -> Section

But I am not able to find this using the UI in Maple 2025, under insert 

Ofcourse, I know I can add section using

                    CTRL .

which works. But I was wondering, where is insert section is in the GUI? Hard to find. I do not see anything called section in the menu there., I tried few of the other items, but so far, can't find section.

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