Advanced Search

nm

12238 Reputation

20 Badges

13 years, 255 days
Contact nm

MaplePrimes Activity


These are questions asked by nm

How to solve this first order ode? ...

nm 12238 Maple
ode dsolve differential-equations
March 17 2026
2 2

Maple 2026 can't solve this first textbook  ode. Book gives solution in the back which Mathematica gives, but for some strange reason, Maple dsolve can't solve it with the IC given. I also tried Maple 2025, it can't solve it.

ode:=diff(y(x),x)*sin(2*x) = 2*y(x)+2*cos(x); 
ic:=y(1/2*Pi) = 0; 
sol:=dsolve([ode,ic]);

No solution. returns ()

But this is the solution from book which Maple verfies is correct

book_sol:=y(x)=tan(x)-sec(x);
odetest(book_sol,[ode,ic])

gives [0,0]

Here is Mathematica also

Why Maple can't solve it? ofcourse it is not a bug not to be able to solve an ode, but Maple being the best ode solver in the world should have been able to solve it. I've also solved it by hand (it is just a linear first order ode) and got same solution. Maple can solve it without the IC. 

So the issue is in resolving constant of integration using IC is where the problem is.

May be someone could find why Maple can't solve for the constant of integration from the IC. Here is the solution without IC which Maple finds with no problem

ode:=diff(y(x),x)*sin(2*x) = 2*y(x)+2*cos(x); 
sol:=dsolve(ode);

How to know the latest version of the on...

nm 12238 Maple
March 15 2026
1 0

Maple online help pages do not show which version of Maple the help pages for.

At the bottom or top of each help page there really should be something to tell the user which Maple version the help pages for.

For example, going to help on ?type and clicking details opens this page

https://www.maplesoft.com/support/help/Maple/view.aspx?path=type#bkmrk2

But I noticed this web page is different from the one I am looking at now on my installed Maple 2026. 

The above online page is missing new types. Here is screen side by side. Once the above web page opens, scolling down a little below where it shows "defined types" and you will see this difference:

You see, the online Maple help page is missing types shown in the installed version of the help page in Maple 2026.

And user has no clue looking at the web page, which version of Maple these help pages are for, as there is no indication any where on the page.

1) Why the web help pages are out of date?

2) Why is there no mention on the page, which Maple version there help pages represent?

why can't dsolve find this solution ...

nm 12238 Maple 2025
ode dsolve differential-equations
March 14 2026
3 2

Maple 2026 and 2025.2 can't solve this ode.  It actually hangs which is worst.

The ode is from a textbook

ode:=x*diff(y(x),x) = y(x)*cos(ln(y(x)/x)); 
dsolve(ode,y(x), singsol=all);

It just gets stuck.

But we see by just inspection that y(x)=x is a solution

odetest(y(x)=x,ode)

Gives zero. I solved this also by hand as HOMOGENEOUS and got y(x)=x

Trace shows Maple hangs in "trying homogeneous D" for some unknown reason

CPU is also running very high, which seems it is stuck in a LOOP internally.

Any one could shed more light what is happening here and why it hangs on this basic ode? I think the hang in loop could indicate a bug.

Any older version of Maple able to solve this?

How to solve this equation?...

nm 12238 Maple 2025
solve realdomain ln
March 07 2026
3 2 
sol:=ln( (y-1)^(1/3)* (y^2+y+1)^(1/3) ) - ln(y) = 2/5* ln(t^2+1)+_C1;
solve( sol,y);

in real domain is fine also. But all my attempts failed. I waited 3-4 minutes each time and stopped it.

Any one can find a trick? Below worksheet showing my attempts and also solution by Mathematica which took 0.3 seconds

Make sure to save all your work first. This problem is known to crash Maple !

> 

restart;
> 

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

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

Warning,  computation interrupted

> 

restart;
> 

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

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

Warning,  computation interrupted

> 

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

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

Warning,  computation interrupted

> 

 


 

Download solve_problem_march_7_2026.mw

 

Explore or Maplet? ...

nm 12238 Maple 2025
explore embedded-components maplets
March 06 2026
1 6

I never used Maplets before.

Been learning Explore, which is OK, but the UI does not look good. Too much white spaces between sliders.  So been looking at Maplets to use instead.

Should one just use Maplets to make interactive demos with sliders, buttons, popup menus and so on or use Explore? Which is better?

I do not waste more time learning Explore more if Maplets is a better choice.

If someone here knows Maplets, here is something I just wrote in Explore.  Could this be coded in Maplets to see how it will look like. It took me 30 minutes to make it using Explore and I am no expert in Explore, so hopefully it should not take someone who knows Maplets much time to produce same thing as Maplet. I wanted to see if the UI will look better or same issues with too wasted spaces between sliders.  I assume with Maplets, there is same concept as Explore, with range of variables, and initial values and so on...

I understand one can run Maplet using Maple viewer without needing to have Maple installed on the PC, so this is an advantage.

> 

restart;
> 

ode_1 := diff(x(t),t) = r*x(t) *(1-(x(t)+beta*y(t))/k1):
ode_2 := diff(y(t),t) = k*y(t) *(1-(y(t)+alpha*x(t))/k2):
> 

Explore(DEtools:-DEplot(
     [ ode_1, ode_2],[x(t),y(t)],t=0..max_time,[[x(0)=x0,y(0)=y0]],
     x=0..max_x, y=0..max_y,'labels'=["Elk","Deer"],'dirfield'=[ngrid,ngrid],
     'arrows'='SLIM', #'smalltwo',
     'axes'='boxed', 'color' = blue,'linecolor'='red',#color of solution
     'obsrange'=false,
     'title'="Lotka -Volterra Model of Competition"
     ),
    parameters=[
     [r=0..5,'controller' = 'slider','minorticks'=.1,'snaptoticks'=true, 'label' = "Elk growth rate r",'showlabels'=false,placement='right'],
     [alpha=0..2,'controller' = 'slider','minorticks'=.1,'snaptoticks'=true, 'label' = "Elk competition alpha",'showlabels'=false,placement='right'],
     [k1=100..1000,'controller' = 'slider','minorticks'=10,'snaptoticks'=true, 'label' = "Elk carrying capacity",'showlabels'=false,placement='right'],
     [k=0..5,'controller' = 'slider','minorticks'=.1,'snaptoticks'=true, 'label' = "Deer growth rate k",'showlabels'=false,placement='right'],
     [beta=0..2,'controller' = 'slider','minorticks'=.1,'snaptoticks'=true, 'label' = "Deer competition beta",'showlabels'=false,placement='right'],
     [k2=100..1000,'controller' = 'slider','minorticks'=10,'snaptoticks'=true, 'label' = "Deer carrying capacity",'showlabels'=false,placement='right'],
     [max_time=1..200,'controller' = 'slider','minorticks'=1,'snaptoticks'=true, 'label' = "max time",'showlabels'=false,placement='left'],
     [max_x=1..1000,'controller' = 'slider','minorticks'=1,'snaptoticks'=true, 'label' = "max x",'showlabels'=false,placement='left'],
     [max_y=1..1000,'controller' = 'slider','minorticks'=1,'snaptoticks'=true, 'label' = "max y",'showlabels'=false,placement='left'],
     [x0=1..200,'controller' = 'slider','minorticks'=1,'snaptoticks'=true, 'label' = "Deer initial population",'showlabels'=false,placement='left'],
     [y0=1..200,'controller' = 'slider','minorticks'=1,'snaptoticks'=true, 'label' = "Elk initial population",'showlabels'=false,placement='left'],
     [ngrid=10..30,'controller' = 'slider','minorticks'=1,'snaptoticks'=true, 'label' = "arrows",'showlabels'=false,placement='left']     
    ],
    initialvalues=[r=0.12,k1=600,alpha=1.5,k2=600,k=0.18,beta=1.2,x0=75,y0=100,ngrid=24,max_x=700,max_y=700,max_time=100],
    'adaptview'=true
);
 

 

Download lotka_volterra.mw

Screen shot of the UI

 

How would the above look using Maplets instead of Explore?

1 2 3 4 5 6 7 Last Page 2 of 217