nm

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These are questions asked by nm

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.
 

interface(version);

`Standard Worksheet Interface, Maple 2025.2, Windows 10, November 11 2025 Build ID 1971053`

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

diff(y(x), x) = x*(x^2+9)^(1/2)

y(-4) = 0

sol:=dsolve([ode,IC]);

y(x) = (1/3)*(x^2+9)^(3/2)-125/3

p:=plot(rhs(sol),'axes'='boxed','labels'=[x,y(x)],'axis'=['gridlines'=['color'='lightblue']],'color' = 'red');

 

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]);  

[-9.94999999999999929 .. 9.94999999999999929, -32.6629164062620561 .. 332.469298224442980]

-9.94999999999999929

9.94999999999999929

-32.6629164062620561

332.469298224442980

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
                );

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
                );

 


 

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