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How to patmatch y(x) ?...

nm 11643 Maple 2025
patmatch
September 20 2025
1 0

I wanted to check that the input  has the pattern   symbol(symbol), which will match any of   y(x), or f(x) or A(B) and so on.

But using patmatch does not work. Using patmatch(h(z),y::symbol(x::symbol),'la');  or even patmatch(h(z),'y'::anything('x'::anything),'la'); all return false. I know I can do patmatch(h(z),func::function(name),'la'); and this returns true, but this matches h(z,r) and matches h(z,r,t) and matches h(z,r,t,u) and so on. 

I wanted to match only   SYMBOL(SYMBOL), i..e. one symbol followed by "(" followed by one symbol followed by closing ")"

For reference, this is what I am looking for 

I know I can use other ways in Maple to do this (may be typematch and and others). But wanted to see if patmatch works on this and why it is failing.

Can this be done using patmatch?

How to obtain this solution using dsolve...

nm 11643 Maple 2025
ode dsolve differential-equations
September 20 2025
0 1

Maple 2025.1 unable to solve this ode. Sympy gives the following two solutions which Maples verifies are correct.

Any trick or option that can help dsolve find these solutions?
 

> 

interface(version);

`Standard Worksheet Interface, Maple 2025.1, Linux, June 12 2025 Build ID 1932578`

> 

restart;
> 

ode:=diff(y(x),x) = (1+cos(x)*sin(y(x)))*tan(y(x));

diff(y(x), x) = (1+cos(x)*sin(y(x)))*tan(y(x))

> 

sol:=dsolve(ode);

> 

sol_1:=y(x)=arcsin( 2*exp(x) / ( c__1 + sqrt(2)*exp(x) * sin(x+Pi/4) ) ) + Pi

y(x) = arcsin(2*exp(x)/(c__1+2^(1/2)*exp(x)*sin(x+(1/4)*Pi)))+Pi

> 

odetest(sol_1,ode)

0

> 

sol_2:=y(x)=arcsin( 2*exp(x) / ( c__1 - sqrt(2)*exp(x) * sin(x+Pi/4) ) ) ;

y(x) = arcsin(2*exp(x)/(c__1-2^(1/2)*exp(x)*sin(x+(1/4)*Pi)))

> 

odetest(sol_2,ode)

0

> 

 


 

Download How_to_find_solution_sept_20_2025.mw

update:

OK, found out how. Needed transformation u(x)=sin(y(x)). Maple probably did not have this in one of the things to try.

 

> 

restart;
> 

ode:=diff(y(x),x) = (1+cos(x)*sin(y(x)))*tan(y(x));
sol:=dsolve(ode);

diff(y(x), x) = (1+cos(x)*sin(y(x)))*tan(y(x))

> 

tr:=y(x)=arcsin(u(x));
PDEtools:-dchange(tr,ode,[u(x)]):
dsolve(%);
sol:=y(x)=arcsin(rhs(%));
odetest(sol,ode)
 

y(x) = arcsin(u(x))

u(x) = -2/(-2*exp(-x)*c__1+sin(x)+cos(x))

y(x) = -arcsin(2/(-2*exp(-x)*c__1+sin(x)+cos(x)))

0


 

Download How_to_find_solution_sept_20_2025_V2.mw

 

 

why can't Maple solve this basic fir...

nm 11643 Maple 2025
ode dsolve implicit
September 02 2025
3 5

Any idea why Maple dsolve can't find solution to this ode? From textbook

The strange thing, it solves if it asked for implicit solution. But the default, will give no solution.

Is this a defect? Should it not have returned the book solution automatically?   How is a user supposed to know the ode has a solution or not, if default call returns no solution?

> 

restart;
> 

interface(version);

`Standard Worksheet Interface, Maple 2025.1, Linux, June 12 2025 Build ID 1932578`

> 

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 1877 and is the same as the version installed in this computer, created 2025, July 11, 19:24 hours Pacific Time.`

> 

restart;
> 

ode:=v(x)*diff(v(x),x) = g;
ic:=v(x__0) = v__0;
sol:=dsolve([ode,ic]);

v(x)*(diff(v(x), x)) = g

v(x__0) = v__0

> 

restart;
> 

ode:=v(x)*diff(v(x),x) = g;
ic:=v(x__0) = v__0;
sol:=dsolve([ode,ic],'implicit');

v(x)*(diff(v(x), x)) = g

v(x__0) = v__0

-2*g*x+v(x)^2+2*g*x__0-v__0^2 = 0

> 

#why did not default call return this?
PDEtools:-Solve(sol,v(x))

v(x) = (2*g*x-2*g*x__0+v__0^2)^(1/2), v(x) = -(2*g*x-2*g*x__0+v__0^2)^(1/2)

Download dsolve_gives_no_solution_sept_2_2025.mw

Why Maple 2025.1 can't solve this fi...

nm 11643 Maple 2025
ode dsolve differential-equations
August 25 2025
2 0

I was surprised that Maple can't solve this first order ode which is exact ode.

I solved by hand and Maple says my solution is correct.

Any one can find why Maple failed to solve this and if older versions can solve it? Also tried implicit option, but that did not help.

> 

interface(version);

`Standard Worksheet Interface, Maple 2025.1, Linux, June 12 2025 Build ID 1932578`

> 

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;
> 

ode:=diff(y(x),x) = (2*sin(2*x)-tan(y(x)))/x/sec(y(x))^2;

diff(y(x), x) = (2*sin(2*x)-tan(y(x)))/(x*sec(y(x))^2)

> 

sol:=dsolve(ode);

> 

mysol:=cos(2*x)+x*tan(y(x))=c__1;

cos(2*x)+x*tan(y(x)) = c__1

> 

odetest(mysol,ode);

0

 

 

Download maple_solving_exact_ode_august_25_2025.mw

Should not dsolve give implicit solution...

nm 11643 Maple 2025
ode dsolve implicit
August 22 2025
0 4

THis is problem from textbook. Maple do not give solution. 

But when asked for implicit solution, it gives one.  Should it not have done this automatically?

> 

interface(version);

`Standard Worksheet Interface, Maple 2025.1, Linux, June 12 2025 Build ID 1932578`

> 

ode:=y(x)*diff(y(x),x) = a;
ic:=y(0) = b;
sol:=dsolve([ode,ic]);

y(x)*(diff(y(x), x)) = a

y(0) = b

> 

sol:=dsolve([ode,ic],'implicit')

-2*a*x+y(x)^2-b^2 = 0

 

 

Download why_no_solution_maple_2025_1.mw

We see now there are two solutions for y(x), since quadratic.

So why dsolve do not solve this and at least give implicit solution automatically? Should this be reported as defect?

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