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Collect using pattern?...

nm 11643 Maple 2025
programming collect
3 hours ago
1 0

is it possible to collect using pattern? For example, given 

How to tell Maple to collect on  r^power terms to produce

This came up in another forum here  and using that other software, it is possible to ask collect to collect on pattern r^_

Is there a way in Maple to collect on all powers of r in the above? Here is worksheet

> 

A:=r^(2*a)+r^2*(1+a+r^(2*a)) + r + a*r;
B:=(1+a)*r+(1+a)*r^2+r^(2*a)+r^(2+2*a);

r^(2*a)+r^2*(1+a+r^(2*a))+r+a*r

(1+a)*r+(1+a)*r^2+r^(2*a)+r^(2+2*a)

> 

simplify(A-B)

0

> 

collect(A,r)

r^2*(1+a+r^(2*a))+(1+a)*r+r^(2*a)

> 

collect(A,r,'distributed')

r^2*(1+a+r^(2*a))+(1+a)*r+r^(2*a)

> 

collect(A,r,'recursive')

r^2*(1+a+r^(2*a))+(1+a)*r+r^(2*a)

> 

collect(A,r,expand)

(1+a+(r^a)^2)*r^2+(1+a)*r+(r^a)^2

> 

collect(A,r^(n::anything))

Error, (in collect) cannot collect r^n::anything

> 

 


 

Download collect_using_pattern.mw

Using that other software:

 

simplify sqrt(1-cos(x)^2) to sqrt(sin(x)...

nm 11643 Maple 2025
simplify simplification trig
December 03 2025
4 10

I do not remember if this came up before. And this is all done in code, without looking at the screen.

Given sqrt(1-cos(x)^2), Maple's simplify does not return sqrt(sin(x)^2), instead it returns ugly result csgn(sin(x))*sin(x) which is correct ofcourse, but why not just return sqrt(sin(x)^2)?  As sqrt(sin(x)^2) is much easier to read than csgn(sin(x))*sin(x).

length of sqrt(1-cos(x)^2) is 29 and length of sqrt(sin(x)^2) is 21.

What Maple simplify seems to do is simplify sqrt(1-cos(x)^2) to sqrt(sin(x)^2) internally, but instead of stopping there, it keeps going and "simplifies" sqrt(sin(x)^2)  to csgn(sin(x))*sin(x).

How to make it stop at sqrt(sin(x)^2)?

Again, this is done in code. Not interactive. code uses simplify() command on most things. 

> 

interface(version)

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

> 

A:=sqrt(1-cos(x)^2)

(1-cos(x)^2)^(1/2)

> 

B:=sqrt(sin(x)^2)

(sin(x)^2)^(1/2)

> 

length(A)

29

> 

length(B)

21

> 

simplify(A)

csgn(sin(x))*sin(x)

> 

simplify(A,trig)

csgn(sin(x))*sin(x)

> 

simplify(A,size)

(1-cos(x)^2)^(1/2)

> 

simplify(A) assuming x>0 and x<Pi

sin(x)

> 

 

 

Download simplify_dec_3_2025.mw

That other system does it better

Is it possible to make simplify do the same in Maple? 

dsolve gives division by zero when using...

nm 11643 Maple 2025
ode dsolve differential-equations
December 02 2025
0 1

DO not know if this is new in Maple 2025.2 or not as I have not looked yet if it is possible to install Maple 2025.1 on my new PC given Maple 2025.2 is already installed.

Found That Maple 2025.2 gives "Error, (in dsolve) numeric exception: division by zero" when asked to solve this ode using Lie symmetry.  The error comes when it tried to 

                        Computing canonical coordinates for the symmetry 

Even if this problem was in earlier Maple versions, this ofcourse should not happen.

> 

interface(version);

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

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1882 and is the same as the version installed in this computer, created 2025, December 1, 6:58 hours Pacific Time.`

> 

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.`

> 

libname;

"C:\Users\me\maple\toolbox\2025\Physics Updates\lib", "C:\Users\me\maple\toolbox\2025\Maple Customer Support Updates\lib", "C:\Program Files\Maple 2025\lib"

> 

restart;
> 

ode:=sin(x)*diff(y(x), x, x) + (2*sin(x) - cos(x))*diff(y(x), x) + (sin(x) - cos(x))*y(x) = exp(-x);

sin(x)*(diff(diff(y(x), x), x))+(2*sin(x)-cos(x))*(diff(y(x), x))+(sin(x)-cos(x))*y(x) = exp(-x)

> 

dsolve(ode)

y(x) = exp(arcsin(cos(x)))*c__2+exp(arcsin(cos(x)))*cos(x)*c__1+exp(arcsin(cos(x)))*(-(Int(csc(x)^2*exp(-arcsin(cos(x))-x), x))*cos(x)+Int(cot(x)*csc(x)*exp(-arcsin(cos(x))-x), x))

> 

dsolve(ode,Lie)

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

 

 

Download division_by_zero_dsolve_maple_2025_2_on_dec_2_2025.mw

why is collect needed to simplify an exp...

nm 11643 Maple 2025
simplify diff
December 01 2025
2 1

I have an expression with y,y',y''. I found that I had to use collect first to make Maple simplifies it more.

Why is that? Is this expected?

> 

interface(version);

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

> 

B:=-(-t^2+1)*(-diff(y(t),t$2)*(-t^2+1)^(1/2)+diff(y(t),t)/(-t^2+1)^(1/2)*t)-(2*(-t^2+1)^(1/2)-t)*diff(y(t),t)*(-t^2+1)^(1/2)+((-t^2+1)^(1/2)-t)*y(t);

-(-t^2+1)*(-(diff(diff(y(t), t), t))*(-t^2+1)^(1/2)+(diff(y(t), t))*t/(-t^2+1)^(1/2))-(2*(-t^2+1)^(1/2)-t)*(diff(y(t), t))*(-t^2+1)^(1/2)+((-t^2+1)^(1/2)-t)*y(t)

> 

simplify(B);

((diff(diff(y(t), t), t))*t^4+2*(diff(y(t), t))*t^2*(-t^2+1)^(1/2)-2*(diff(diff(y(t), t), t))*t^2-y(t)*t^2-y(t)*(-t^2+1)^(1/2)*t-2*(diff(y(t), t))*(-t^2+1)^(1/2)+diff(diff(y(t), t), t)+y(t))/(-t^2+1)^(1/2)

> 

B:=collect(B,{diff(y(t),t$2),diff(y(t),t),y(t)},'distributed'):
simplify(B);

2*(t^2-1)*(diff(y(t), t))+((-t^2+1)^(1/2)-t)*y(t)+(-t^2+1)^(3/2)*(diff(diff(y(t), t), t))


Download why_collect_is_needed_to_simplify_more_maple_2025_2_nov_30_2025.mw

Notice how much simpler the result when doing collect first.

Screen reader Maple on windows 10?...

nm 11643 Maple 2025
gui windows10
November 30 2025
0 1

I've seen many here recommend using the screen reader for Maple 2025. So this is first time I tried it.

Clicked on this second icon in my windows 10 start menu

Maple came up using the old UI, which is good:

But here comes the big problem. The file->Open menu does not work. It automatically opened in location which is not what I want. I wanted to navigate to different place on my PC. But anything I click on just generates loud beep and does nothing. Can't type anything to change location either.

So can't open any file. Not only that, It is stuck and can't even close the windows. Can't get out. Everything is stuck. 

It could be because I have 2 monitors. I had this open on the second monitor on the right. Everything on the second monitor now do not respond like Maple. Luckily, on the left monitor I was able to start task manager and kill Maple in order to get out of this hang.    

Basically screen reader does not work at all for me. If I can't open a file.

It could be due to using 2 monitors. I do not know.

Does file open work for others?

Here is small movie.

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