Do not know if this known or reported or not. Just in case. Here is an example where odetest gives internal error when adding integer to assuming. 

Maple 2025.2. Firewall will not let me upload now. Here is code

sol:=y(x) = -4/9*I*(x+1)^(1/4)*(x-1)^(1/4)*2^(1/2)*x^2+4/9*(x+1)^(1/4)*(x-1)^(1/4)*2^(1/2)*x^2+4/9*I*(x+1)^(1/4)*(x-1)^(1/4)*2^(1/2)+1/9*x^4-4/9*(x+1)^(1/4)*(x-1)^(1/4)*2^(1/2)-16/9*I*(x+1)^(1/2)*(x-1)^(1/2)-2/9*x^2+1/9;
ode:=(-x^2+1)*diff(y(x),x)+x*y(x) = x*(-x^2+1)*y(x)^(1/2);
IC:=y(0) = 1;

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

Screen shot

I wanted to trick odetest and see what it does. I gave it solution to ode with IC. The solution was in form of implicit solution.

odetest verified it.

Then I solved for y(x) from the implicit solution and passed each now explicit solution to odetest, now it does not verify either one. (two explicit solutions resulted)

I would have thought that odetest to not verify the implicit solution as well. Is this a bug or an expected behavior when using implicit?

Does this mean, to be safe, one should try to solve for y(x) explicitly before using odetest? But sometimes this can be expensive or not possible nor practical to do as implicit solution can be complicated to solve for y(x).

Maple 2025.2 on windows 10.

Firewall now suddently will not let me upload a worksheet again for some reason. Firewall did not have a problem yesterday, but today it complained.

So here code and screen shot

restart;
ode:=2*y(x) + 2*x*y(x)^2 + (2*x + 2*x^2*y(x))*diff(y(x), x) = 0;
IC:=y(0) = 1;
maple_sol:=dsolve([ode,IC]);
#                         maple_sol := ()

my_sol_1:=x*y(x)*(2+y(x)*x)=0;
odetest(my_sol_1,[ode,IC])

#                             [0, 0]

PDEtools:-Solve(my_sol_1,y(x));
map(X->odetest(X,[ode,IC]),[%])

#   [[0, 1], [0, undefined]]

Hi Maplesoft Support / Community,

I've encountered a critical and bizarre bug involving Bits:-And correctness on large integers (~30 digits) derived from repeated integerdivq2exp operations.

• Maple 2023 (Linux x86_64)
• Maple 2025 (Linux x86_64)
• Maple 2025 (Windows x86_64)

The correctness of Bits:-And depends on the order of execution. 

(See attached common.mpl, bug_test2.mpl, bug_test3.mpl logic).

Case "Fail" (bug_test2.mpl):

1. Run operation (loops `integerdivq2exp`).
2. Print result num1 (semicolon).
3. Define num1_clean (hardcoded same value).
4. Bits:-And(num1) -> INCORRECT.
5. Bits:-And(num1_clean) -> INCORRECT.

Case "Pass" (bug_test3.mpl):

1. Define num1_clean.
2. Run operation (loops integerdivq2exp).
3. Bits:-And(num1) -> CORRECT.
4. Bits:-And(num1_clean) -> CORRECT.

The same behaviour can be observed in Worksheet mode using read.  (See worksheet_driver.mw)

But the result cannot be reproduced if not using read. (See worksheet_version.mw and worksheet_version2.mw)

Code below:

N := 2100:
n := 1000:
num := rand(0 .. 2^N)():
operation := proc(num, n)
    local q, k;
    q := num;
    for k from 1 to 2 do
        q := integerdivq2exp(q, n); 
    end do;
    q;
end proc:

read "common.mpl";

num1 := operation(num, n);
num1_clean := 1083029963437854242395921050992;

num1_clean_And_result := Bits:-And(num1_clean, integermul2exp(1, n) - 1);
num1_And_result := Bits:-And(num1, integermul2exp(1, n) - 1);

##################################

expected_result := irem(num1_clean, integermul2exp(1, n));

if num1 <> num1_clean then
    error "num1 does not match num1_clean";
end if;
print("num1 matches num1_clean");

if num1_And_result <> num1_clean_And_result then
    error "num1_And_result does not match num1_clean_And_result";
end if;
print("num1_And_result matches num1_clean_And_result");

if num1_And_result <> expected_result then
    error "num1_And_result does not match expected_result";
end if;
print("num1_And_result matches expected_result");

read "common.mpl";

num1_clean := 1083029963437854242395921050992:
num1 := operation(num, n):

num1_clean_And_result := Bits:-And(num1_clean, integermul2exp(1, n) - 1):
num1_And_result := Bits:-And(num1, integermul2exp(1, n) - 1);

##################################

expected_result := irem(num1_clean, integermul2exp(1, n));

if num1 <> num1_clean then
    error "num1 does not match num1_clean";
end if;
print("num1 matches num1_clean");

if num1_And_result <> num1_clean_And_result then
    error "num1_And_result does not match num1_clean_And_result";
end if;
print("num1_And_result matches num1_clean_And_result");

if num1_And_result <> expected_result then
    error "num1_And_result does not match expected_result";
end if;
print("num1_And_result matches expected_result");

I noticed today only 2 cases where calling simplify, with no options, made things worst.

Just trying to understand why.

Here is one example. Solved an ode. when calling odetest on this solution, it gives zero. But if the solution is simplified first, then odetest no longer gives zero. And it is actually hard to find a trick to make it become zero so far.

But the question is: Is this to be expected sometimes? I use simplify sporadically, but like to get smaller  expression at one point. But now I am not sure if I should even do that.

Could this be a problem in simplify itself somehow?

Here is an example.

Download why_simplify_changes_things_at_dec_27_2025.mw

Notice how much simpler the solution becomes after calling simplify. I'd like to use that. But for some reason, odetest now fails to verify the simpler version. Which tells me simplify did something which made the solution not valid.

Here is second example, where calling simplify in betwen did not give zero as expected.

Download why_simplify_changes_things_at_dec_27_2025_V2.mw

Just trying to understand why this happens and if this is something that could happen sometimes? May be one should avoid calling simplify in middle of computation and let the user decide if they want to simplify the final result or not?

I do not remember now if this came up before or not. But this has been a problem in Maple for years.

when doing infolevel[dsolve]:=5 and call dsolve(), some of the display on the screen is missing commas and multiplication sign and who know what else. Since it is all replace by space.

This happens only to part of the display. Here is an example (must use restart each time to see the full display)

restart;
ode:=diff(y(x),x) = (-y(x)^2+4*a*x)^2/y(x); 
infolevel[dsolve]:=5;
dsolve(ode);

Here is the output. Using worksheet, V 2025.2 on windows 10 (I am only showing part of the output which has the problem)

Looking at the line where is says "-> Calling odsolve ". Notice the rest. diff(diff(y(x) x) x)  should be diff(diff(y(x),x),x)  and the end of the line has diff(y(x) x)) y(x)  . So one can guess this should be  diff(y(x),x))*y(x) or it could be diff(y(x),x))/y(x) or may be something else.

THis cause a problem when trying to copy it and use it to try it.

Is there something one can do  in settings to fix this part of the display? so nothing is replace by space?

Maple 2025.2 on windows 10

I also tried this in document mode instead of worksheet. Same result. 

Update

Found where this comes from. From `odsolve/2` proc, line 21.

THis is how to see it.

restart;

infolevel[dsolve]:=5;
ode:=diff(y(x),x)=x*y(x)+1/y(x)+y(x)^3;
stopat(`odsolve/2`);
dsolve(ode)

Now the debugger will come up. Then do in the debugger:

stopat 21

Click continue, you will now stop at this line

In the worksheet it now shows as

So something in 

 `ODEtools/userinfo`(2,dsolve,`-> Calling odsolve with the ODE`,A);

Is not right. Also the last y(x) was meant to be second item in A which is expression sequence. But in worksheet it all display on one line with no commas between.,

So better formating in ODEtools/useinfo is needed here. For some reason, commas are all replaced by spaces.

Is it possible to obtain integral of sqrt(1+sin(x)^2) in Maple as known result of elliptic integral of the second kind  E(x,-1) ?

Maple 2025 gives

integrand:=sqrt(1+sin(x)^2);
anti:=int(integrand,x);
anti:=simplify(anti);

Not able to differentiate back:

diff(anti,x);
simplify(%)

Google says:

And the above is also what Mathematica gives

Is it possible to obtain E(x,-1) also in Maple for this integral?

Maple 2025.2

Not able to make an example, since it depends of code flow and not able to reproduce it in small code. I spend hrs trying to make one. It depends on how memory is arranged and this problem shows only when running my large program.

But I can show screen shots from a debugging session showing clearly the problem, and the solution I found.

Maple was giving this result, when calling simplify to simplify a matrix:

Notice what happend. There was a matrix [3/2,-1,-3/2,0],[0,0,0,0],[-2,2,2,0]] before that was simplfied.

Next iteration called simplify on modified version of the matrix, which is  [3/2,-1,-3/2,0],[0,0,0,0],[0,2/3,0,0]].  (called e in the above).

But simplify returned as result the old copy. Which is completely wrong.

It simplified  [3/2,-1,-3/2,0],[0,0,0,0],[0,2/3,0,0]]  to  [3/2,-1,-3/2,0],[0,0,0,0],[-2,2,2,0]]  !

Now see what happes when calling forget(simplify)

You see, now it simplfies it correctly. (there is actually nothing to simplify, so it returned back same matrix as expected, and no copy it had in memory).

So now I went over all my code, and everywhere it calls simplify, added 

     forget(simplify)

right after each call.

Problem fixed.

May be someone can shed a light on why this happens. Any information needed will try to provide. I can reproduce this each time but using the debugger.

restart;

ode:=diff(y(x),x) = 3*(y(x)*x)^(1/2); 
IC:=y(0)=2;
sol:=dsolve([ode,IC])

This is a good example of how Maple result looks different depending on what calls to Maple were made before.

I can't upload worksheet so have to show code and screen shot. Compare the screen shot below. Maple 2025.2. Same exact input., In first example the polynomial terms display in different order compared to the second example, even though the same exact input is used.

Clearly the first example is because Maple remembered this polynomial in its remember table somewhere before due to earlier call, and did not want to make new copy since it is same polynomial?

But I do want to make new polynomial. The old copy/order this polynomial in Maple internal tables is getting in the way.

But do not know how to tell Maple to clear its cache so I get same display as in the second example. I know both answers is the same. But the issue is why it displays different.

How could I get same output from first example as in the second one? What do I need to clear? I tried forget(Student:-Precalculus:-CompleteSquare) but this had no effect. ALso tried forget(all); also forget(all,forgetpermanent = true,reinitialize=true); also forget(Student:-Precalculus:-CompleteSquare,subfunctions=true);

code

restart;

eq := x^2 + y^2 + z^2 - 2*x + 8*y - 6*z - 30 = 0:
eq:=Student:-Precalculus:-CompleteSquare(eq):
e1:=convert(indets(%,`^`),list):
e2:=zip((a,b)->a=b,e1,[X,Y,Z]):
e3:=sort(eval(eq,e2));
e4:=map(X->rhs(X)=lhs(X),e2);
eval(e3,e4);

restart;

e3 := X + Y + Z - 56 = 0;
e4 := [X = (x - 1)^2, Y = (y + 4)^2, Z = (z - 3)^2];
eval(e3,e4);

[moderator: duplicate of this earlier question]

What is the current status of SupportTools? Is this something that still brings fixes in Maple before official release?

I am asking because there have not been an update to ST since June 23, 2025. Almost 6 months ago.

Should one still check for current version of SupportTools, is it still being updated or not? If not, then what does SupportTools package actualy do or contain if it is no longer needed/used? 

This is all fussy for me, and some clarification for users will be good to better understand the role of this package.

odetest does not want to verify this maple solution against the IC.  Anyone could find why or a trick to get [0,0] from odetest?

Can not upload worksheet due to firewall at Mapleprime issue. Here the code and screen shot.

ode := diff(y(x),x) +cos(1/exp(2*x))*y(x) = sin(1/exp(x));
IC := a*D(y)(x0)+ c*y(x0) = b*y0;
maple_sol:=dsolve([ode,IC],y(x));
the_residue:=odetest(maple_sol,[ode,IC]);

#not zero, also simplify did not give zero

using regular expression in Maple is little annoying, because one has to escape \ in the regx string itself, which makes it more complicated compared to other languages. For example

StringTools:-RegMatch("^\[.*\]$","[A]")

gives false. But

StringTools:-RegMatch("^\\[.*\\]$","[A]")

gives true.

Other languages have special function to generate the regx itself, which does not require escaping the \ when writing the regx Which makes it easier to see the regx (escaping is done under the cover). like this

Since all places and web sites that show examples of regx., do not have to escape \ before using, it will be good if Maple adds such special new function to StringTools to generate regx like the above so users do not have to remember to escape \.   

It is hard enough to use regx without having to also remember to escape things.

I could not find such a function in Maple. Does one exist?

Maple 2025.2

I use plot(sol,...) to plot solution of ode. I do not give x or y ranges and let Maple figure the best values. Then use the command 

T:=rhs~(indets(p, identical("originalview")=anything))[];    

To extract the x and y ranges used and then use these in the command DEtools:-DEplot(....)

The plot() command shows the solution plot fully (in this example below, the left and right sides).

But the  DEtools:-DEplot(....) only shows part of the solution on top of the slope field arrows.  Even though the same x and y ranges is used.

I found that if I increase the y range for the DEtools:-DEplot(....) by a little bit, now the full solution shows, which is same as plot command generated.

Since I am doing all this in code, without looking, I am first plotting the solution using plot() and then use the ranges generated for DEtools:-DEplot(....).

If I do not use the y range in DEtools:-DEplot(....) but only use the x range, sometimes it works and sometimes Maple gives warnings. (depending on the solution). So I am  back to using the ranges generated by plot() command to be safe.

Here is an example to show this problem

ode:=diff(y(x),x) = x*(x^2+9)^(1/2);
IC:=y(-4) = 0;
sol:=dsolve([ode,IC]);
p:=plot(rhs(sol),'axes'='boxed','labels'=[x,y(x)],'axis'=['gridlines'=['color'='lightblue']],'color' = 'red');

Now the x and y ranges used above is extraced

T:=rhs~(indets(p, identical("originalview")=anything))[];      
from_x := op(1,T[1]);
to_x   := op(2,T[1]);
from_y := op(1,T[2]);        
to_y   := op(2,T[2]);  

#gives

      T := [-9.94999999999999929 .. 9.94999999999999929, 
        -32.6629164062620561 .. 332.469298224442980]


                 from_x := -9.94999999999999929
                  to_x := 9.94999999999999929
                 from_y := -32.6629164062620561
                  to_y := 332.469298224442980

These are used in the DEplot

DEtools:-DEplot(ode,[y(x)],x=from_x..to_x,y=from_y ..to_y ,[IC],
                'dirfield'=[15,15],
                'labels'=[x,y(x)],
                'axes' = 'boxed',                
                'arrows'='smalltwo', #'curve', 
                'color' = 'blue',#color of arrows
                'linecolor'='red'#color of solution
                );

Notice how the solution (red line) is truncated.  It turns out in this case adding say 10% to the y range, it now shows the solution like this

DEtools:-DEplot(ode,[y(x)],x=from_x..to_x,y=from_y-(0.1*abs(from_y)) ..to_y ,[IC],
                'dirfield'=[15,15],
                'labels'=[x,y(x)],
                'axes' = 'boxed',                
                'arrows'='smalltwo', #'curve', 
                'color' = 'blue',#color of arrows
                'linecolor'='red'#color of solution
                );

But I do not know if this trick will work for each example. 

As I said, I can not give the y range to DEplot, then in this example, it will now show the full solution. But I have examples where this can cause warnings.

The question is, why giving same y range used by plot to DEplot cause the solution (red line) to truncate? Why one has to increase the y range to make it show the full solution?

Is there a better method that the above to make DEplot show full solution same as plot() does? 

Maple 2025.2

ps. I just tried upload the worksheet and now it works! it looks like mapleprimes web site is fixed.
 

Download example_phase_plot.mw

How to explain this strange behavior?   odetest(sol,ode) does not give zero. But odetest(sol,[ode,IC]) gives [0,0]

Same solution and same ode. Why adding IC, now odetest says solution verifies the ode, but without adding IC, it does not give zero right away. I know I can simplify the result to zero. But the point is that it should have given zero right away, because that is what it did when adding IC.

Should it not have given zero in first case also?

Can't upload worksheet due to security. Here is code and screen shot

ode := diff(y(x),x) + cos(1/exp(2*x))*y(x) = sin(1/exp(x));
IC := a*D(y)(x0)+c*y(x0) = b*y0;
sol:=y(x) = ((-cos(exp(-2*x0))*a + c)*Int(sin(exp(-tau))*exp(-1/2*Ci(exp(-2*tau))), tau = 0 .. x0) + Int(sin(exp(-tau))*exp(-1/2*Ci(exp(-2*tau))), tau = 0 .. x)*(cos(exp(-2*x0))*a - c) + exp(-1/2*Ci(exp(-2*x0)))*(a*sin(exp(-x0)) - b*y0))*exp(1/2*Ci(exp(-2*x)))/(cos(exp(-2*x0))*a - c);

odetest(sol,ode);

#not zero

#now

odetest(sol,[ode,IC]);

#gives [0,0]

Could someone please check if these are new in Maple 2025.2? I am on windows 10.

eqs:=[_C1+_C2 = 0, _C1*exp(3^(1/2)*((cos(1/6*Pi*3^(1/2))-1)*(cos(1/6*Pi*3^(1/2))+1))^(1/2)/(cos(1/6*Pi*3^(1/2))-1)^(1/2)/(cos(1/6*Pi*3^(1/2))+1)^(1/2)*ln(cos(1/6*Pi*3^(1/2))+(cos(1/6*Pi*3^(1/2))^2-1)^(1/2)))+_C2*exp(-3^(1/2)*((cos(1/6*Pi*3^(1/2))-1)*(cos(1/6*Pi*3^(1/2))+1))^(1/2)/(cos(1/6*Pi*3^(1/2))-1)^(1/2)/(cos(1/6*Pi*3^(1/2))+1)^(1/2)*ln(cos(1/6*Pi*3^(1/2))+(cos(1/6*Pi*3^(1/2))^2-1)^(1/2))) = 4];
c:=[_C1, _C2];
solve(eqs,c);

#Error, (in convert/real_rat) too many levels of recursion

And

eqs:= [3^(1/4*3^(1/2))*exp(3/4*Pi)*_C1-1/3*exp(3/4*Pi)*3^(-1/4*3^(1/2)+1/2
)*_C2 = 1, _C1/(cos(1/3*Pi*3^(1/2))-1)^(1/4)/(cos(1/3*Pi*3^(1/2))+1)^(1/4)*exp(
3/4*Pi-1/2*Pi*3^(1/2))*(cos(1/3*Pi*3^(1/2))^2-1)^(1/4)*3^(1/4*3^(1/2))*((cos(1/
3*Pi*3^(1/2))^2-1)^(1/2)+cos(1/3*Pi*3^(1/2)))^(1/2*3^(1/2))-_C2*3^(-1/2-1/4*3^(
1/2))/(cos(1/3*Pi*3^(1/2))-1)^(1/4)/(cos(1/3*Pi*3^(1/2))+1)^(1/4)*(cos(1/3*Pi*3
^(1/2))^2-1)^(1/4)*exp(3/4*Pi-1/2*Pi*3^(1/2))*((cos(1/3*Pi*3^(1/2))^2-1)^(1/2)+
cos(1/3*Pi*3^(1/2)))^(-1/2*3^(1/2)) = 5*exp(-1/2*Pi*3^(1/2))]:
c:=[_C1, _C2];

solve(eqs,c)

#Error, (in convert/real_rat) too many levels of recursion

And

eqs:=[3^(1/2*3^(1/2))*exp(1/2*Pi)*_C1-1/6*3^(-1/2*3^(1/2)+1/2)*exp(1/2*Pi
)*_C2 = 5, _C1/(cos(1/6*Pi*3^(1/2))-1)^(1/4)/(cos(1/6*Pi*3^(1/2))+1)^(1/4)*exp(
1/2*Pi-1/6*Pi*3^(1/2))*(cos(1/6*Pi*3^(1/2))^2-1)^(1/4)*3^(1/2*3^(1/2))*((cos(1/
6*Pi*3^(1/2))^2-1)^(1/2)+cos(1/6*Pi*3^(1/2)))^(3^(1/2))-1/6*_C2*3^(-1/2*3^(1/2)
+1/2)/(cos(1/6*Pi*3^(1/2))-1)^(1/4)/(cos(1/6*Pi*3^(1/2))+1)^(1/4)*exp(1/2*Pi-1/
6*Pi*3^(1/2))*(cos(1/6*Pi*3^(1/2))^2-1)^(1/4)*((cos(1/6*Pi*3^(1/2))^2-1)^(1/2)+
cos(1/6*Pi*3^(1/2)))^(-3^(1/2)) = 2*exp(-1/6*Pi*3^(1/2))]:
c:=[_C1, _C2];

solve(eqs,c)

Trace shows they are coming from Algebraic: best unknown/equation

Cannot upload worksheet due to security. Here is screen shot