Maple 2023 Questions and Posts

These are Posts and Questions associated with the product, Maple 2023

I have a pretty ugly nested integral (in my opinion) that I am trying to compute. I thought that I simplified the problem to an easier siutation however during my attempted calculations I am recieving: "Error, (in evalf/int) cannot handle unevaluated name `L` in evalhf

I am unsure where this is coming from, I would assume something in procedure or my attempted use of unapply is incorrect. Any comments are welcome, including those that state I am doing this entirely incorrectly. 

Thanks. 

NestedError.mw

I need to highlight all terms that contain eta, my variable, for example (A0)+(A1)*1/eta+(A2)*1/eta^2+...(An)**1/eta^n and so on in my expression call from P. However, when I select eta through the collect command, maple is unable to carry out the command.

P := expand((cosh(k*eta) + alpha*m*sinh(k*eta)/eta)^3);
P := convert(P, exp);
P := expand(P);
P := collect(P, eta);
P := combine(P);

Once these have are in evidence I need to select the coefficients A0, A1, A2, etc. How to proceed if eta are in the denominator and maple does not work with this possibility? This it'was my tentative

B0 := subs(eta = 0, P);

B1 := coeff(P, eta)

B2 := coeff(P, eta^2)

I actually tested the possibility of  1/eta instead of  eta and it didn't work

I am an ophthalmologist and a novice in programing. I am having a problem obtaining the x-y coordinate equations for each of the fitted Splines.  I can send the raw data and MapleSoft work sheet for which I need the individual spline equations, in x-y coodinates not parametric format and also need to be able to plot the splines on the raw data. I will pay for the service. Can you please obtain the x-y Cartesian equations for each of the fitted Splines and give me a step-wise method for obtaining them?  I am unable to attach the raw data and the worksheet to this email.  Please send me your personal email so that I can send them.

Your assistance is most appreciated. 

With my best,
Ron
Ronald A Schachar MD , PhD
7241 Encelia Drive
La Jolla, CA 92037
Cell: (858) 784-1705
Email: ron@2ras.com

WHen using _self in object, help says

"As of Maple 2021, if the method has a formal parameter named _self, references
to its object's local or exported variables may be written without prefixing them.
That is, _self:-variable may be written as just variable. Maple will
add the self:- prefix internally when the method is simplified."

And the above is true for all static methods inside an object module, except for ModuleCopy which is also static.

It seems ModuleCopy is special. But why?  I am thinking it is because at time this is called, the object itself does not yet exist, but for all other methods, the object by then is fully constructed. But wanted to be sure.

Here is an example

restart;

person := module()
option object;
local  m_name::string;
local  m_age::integer;
export ModuleCopy :: static := proc(_self :: person
                                   , proto :: person, name::string, age::integer,$
                                )
         m_age := age;
         m_name := name;
    end proc;

export name::static:= proc(_self, $);
    RETURN(m_name); #no need to write _self:-m_name;
    end proc;

export age::static:= proc(_self, $);
    RETURN(m_age); #no need to write _self:-m_age;
    end proc;

export set_name::static:= proc(_self, name, $);
    m_name := name;   #no need to write _self:-m_name := name
    NULL;
    end proc;

export process::static:=proc(_self,$)
   print("name is ",m_name," age is ",m_age);
end proc;

end module:

And now


o:=Object(person,"me",10);

Error, static procedure `ModuleCopy` refers to non-static local or export `m_age::integer` in surrounding scope

Changing ModuleCopy to

export ModuleCopy :: static := proc(_self :: person
                                   , proto :: person, name::string, age::integer,$
                                )
         _self:-m_age := age;
         _self:-m_name := name;
    end proc;

Now there is no error. But notice that in all other static methods, I can write  m_name directly without using _self:-m_name;

I looked at help page for ModuleCopy but see no mention of this.

Why ModuleCopy is different?

Maple 2023.2 on windows 10

Can you generate equation numbers for inline equations?

Folks,

What is the simplist Maple code needed to isolate a vector that has two components?  See below:

Vector[column](2, [25.00000000*pi*r/(r^2 + z^2), 25.00000000*pi*z/(r^2 + z^2)])

I want to get the magnitude of this vector which is simply the square root of the sum of the squares of the individual components as shown above.

How do I do that?

Chris

I wish to substitute only the base of the ifactor expression like the following

lst := [24300, 18907875, 151200, 147000]

[24300, 18907875, 151200, 147000]

(1)

map(ifactor, lst)

[``(2)^2*``(3)^5*``(5)^2, ``(3)^2*``(5)^3*``(7)^5, ``(2)^5*``(3)^3*``(5)^2*``(7), ``(2)^3*``(3)*``(5)^3*``(7)^2]

(2)

subs(2 = x, %)

[``(x)^x*``(3)^5*``(5)^x, ``(3)^x*``(5)^3*``(7)^5, ``(x)^5*``(3)^3*``(5)^x*``(7), ``(x)^3*``(3)*``(5)^3*``(7)^x]

(3)

I wish my results to be

[x^2*3^5*5^2, 3^2*5^3*7^5, 7*x^5*3^3*5^2, 3*x^3*5^3*7^2]

[6075*x^2, 18907875, 4725*x^5, 18375*x^3]

(4)

such that

subs(x = 2, %)

[24300, 18907875, 151200, 147000]

(5)

evalb(% = lst)

true

(6)

NULL

Download SubsExample.mw

If there a way to do that? I understand that there is a command ifactors which gives me more control, but the form of the result is rather inconvenient. I hope there is a more direct way to do the aforementioned operation.

In Maple 2023 I haven't been able to sign in to the Maple Cloud.
In Maple 2022 there was no problem. In fact in my Maple 2022.2 I'm actually signed in right now.

I need this to get updates to the Physics updates. 
The toolbar in 2023.2 has a grayed out icon saying "Sign in". Nothing happens if I click on it.

PS. I'm also signed in right now to Maple 2021.2. So the problem couldn't be that I cannot be logged in to more than one Maple release.

According to the documentation of MmaTranslator:-Mma:-PolynomialReduce, this command yields . However, 

restart;
MmaTranslator:-Mma:-PolynomialReduce(x**2+y**2,{x-y,y+a});
 = 
                       [         2    2]
                       [[0, 0], x  + y ]

In[1]:= PolynomialReduce[x^2+y^2,{x-y,y+a}](*Mathematica*)

Out[1]= {{x + y, -2 a + 2 y}, 2 a^2}

In SymPy and in MuPAD: 

The output of both is the same as that of Mma; only the result given by Maple is inconsistent with Mathematica's. 

The example above is so simple that the desired result can be found simply by hand. Here is a larger example: 
Given two polynomials .txt and .txt, as well as a list of polynomials .txt, I would like to evaluate 

# Suppose that one has downloaded these three files. 
poly1, poly2 := fscanf("poly1.txt", "%a")[], fscanf("poly2.txt", "%a")[]:
pList := MmaTranslator:-Mma:-ReadList("pList.txt"):
MmaTranslator:-Mma:-PolynomialReduce((a - poly1)*(a - poly2), pList);

 But its result is just “[[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], ]”, while when a=0 it should be “[[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 2, 1, 1, 1, 1, 0, 0, 0, 1, 2, 1, 0, 2, 2, 3, 1, 1, 1, 2, 1, 0, 0, 0, 1, 1, 2, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0], 0]”.
So why does  return a distinct value?

How would I solve for the product of two terms ( s*V or s^2*V). This is a simple example but I would be applying this on much higher order equations.

     V = Vx/(a*s^2 + b*s + c)

Hi:

I am using solve(...,allsolutions)

and Maple is giving me the default "_Z1~" as part of the solution. No problem.

But when I go back and run the same statement again without a restart, it gives me "_Z2~" and my program fails because it is looking to substitute a value for "_Z1".

How do I reset the naming convention without restarting so I can get the same output each time I run the same statement. (BTW: The same thing happens with Veil where it increments the indices of the Veil symbol each time you run the same statement)..

Thank you.

I am really confused by this behavior. Should the solution be different when calling dsolve(ode) vs. dsolve(ode,[x(t),y(t)]) where here ode is list of two coupled first order ode's?

Maple shows the solutions in reverse order in one case vs. the other. I do not see why adding [x(t),y(t)] should make x(t) solution now y(t)'s and y(t) solution now x(t)'s.  Here is an example

Here is worksheet. I just find the out changing very confusing. Should not the same solution for x(t) and y(t) remain the same regardless of adding the second option as list of not? What is the logic behaind this change or order, and how it one to know which is the correct one as they look different.

``

interface(version);

`Standard Worksheet Interface, Maple 2023.2, Windows 10, October 25 2023 Build ID 1753458`

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1592 and is the same as the version installed in this computer, created 2023, November 27, 3:41 hours Pacific Time.`

restart;

20440

ode :=[diff(x(t), t) = (3*x(t))/2 + 2*y(t), diff(y(t), t) = x(t)/2 + y(t)]

[diff(x(t), t) = (3/2)*x(t)+2*y(t), diff(y(t), t) = (1/2)*x(t)+y(t)]

simplify(dsolve(ode,[x(t),y(t)]));

{x(t) = -(1/2)*c__2*(17^(1/2)-1)*exp(-(1/4)*(-5+17^(1/2))*t)+(1/2)*c__1*exp((1/4)*(5+17^(1/2))*t)*(17^(1/2)+1), y(t) = c__1*exp((1/4)*(5+17^(1/2))*t)+c__2*exp(-(1/4)*(-5+17^(1/2))*t)}

simplify(dsolve(ode));

{x(t) = c__1*exp((1/4)*(5+17^(1/2))*t)+c__2*exp(-(1/4)*(-5+17^(1/2))*t), y(t) = -(1/8)*c__2*(17^(1/2)+1)*exp(-(1/4)*(-5+17^(1/2))*t)+(1/8)*c__1*exp((1/4)*(5+17^(1/2))*t)*(17^(1/2)-1)}

#when using SET instead of LIST, then same solutions come out as above
simplify(dsolve(ode,{x(t),y(t)}));

{x(t) = c__1*exp((1/4)*(5+17^(1/2))*t)+c__2*exp(-(1/4)*(-5+17^(1/2))*t), y(t) = -(1/8)*c__2*(17^(1/2)+1)*exp(-(1/4)*(-5+17^(1/2))*t)+(1/8)*c__1*exp((1/4)*(5+17^(1/2))*t)*(17^(1/2)-1)}

 

Download why_solution_changes_nov_27_2023.mw

I want to creat an interactive document for students. When user clicks in a coordinate-system a point shall come up. For this I need the relative (or absolute) coordinates of the actual mouse position. I cannot find the command for this. In other languages it is like getmousex, getmousey. Can anyone help, please?

As a part of my learning curve, I am trying to play with extending Maple's BernsteinBasis, which has only a limited support right now (BernsteinBasis - Maple Help (maplesoft.com)).

My goal is to implement basis operation on polynomials in Bernstein basis, so that derivatives, integrals and products of polynomials in  BernsteinBasis would be again expressed in BernsteinBasis.

While it looks like it is relatively easy to extend diff procedure, by using `diff/BernsteinBasis`, I didn't find anything similar for the int. Is there something like `int/BernsteinBasis`?

The problem is that when I am trying to implement my own int procedure in a module that  would extend standard int, it seems I need to manually implement logic for (at very least) linearity, so that int(p(x) + q(x), x) would decay into int(p(x), x) + int(q(x), x ) (I probably don't need more complex rewriting rules). So before trying this approach, is there any easy way such as with diff?
 

restart;

read("C:\\Users\\Igor\\Maple\\BernsteinPolynomials.mpl");

_m2141342686560

(1)

# General formula
diff(BernsteinBasis(k, n, a, b, x), x);

n*BernsteinBasis(k-1, n-1, a, b, x)/(b-a)-n*BernsteinBasis(k, n-1, a, b, x)/(b-a)

(2)

# In expressions
diff(2*x*BernsteinBasis(1, 2, 0, 1, x) + BernsteinBasis(2, 2, 0, 1, x), x);

2*BernsteinBasis(1, 2, 0, 1, x)+2*x*(2*BernsteinBasis(0, 1, 0, 1, x)-2*BernsteinBasis(1, 1, 0, 1, x))+2*BernsteinBasis(1, 1, 0, 1, x)

(3)

# Convertion to MatrixPolynomialObject works
p := diff(BernsteinBasis(1, 2, 0, 1, x) + BernsteinBasis(2, 2, 0, 1, x), x);
P := convert(p, MatrixPolynomialObject, x);
P:-Value(a);

p := 2*BernsteinBasis(0, 1, 0, 1, x)

 

P := Record(Value = Default[value], Variable = x, Degree = 1, Coefficient = coe, Dimension = [1, 1], Basis = BernsteinBasis, BasisParameters = [1, 0, 1], IsMonic = mon, OutputOptions = [shape = [], storage = rectangular, order = Fortran_order, fill = 0, attributes = []])

 

Matrix(%id = 36893490288797933188)

(4)

# Now, integrataion
with(BernsteinPolynomials);

[int]

(5)

# Still works
int(x^2, x);

(1/3)*x^3

(6)

# Not implemented but will be added later...
int(BernsteinBasis(1, 2, 0, 1, x), x);

"Will be implemented here..."

 

int(BernsteinBasis(1, 2, 0, 1, x), x)

(7)

# This is the problem: how to implement basis properties such as linearity?
int(2 * BernsteinBasis(1, 2, 0, 1, x), x);

int(2*BernsteinBasis(1, 2, 0, 1, x), x)

(8)

 

 

BernsteinPolynomials := module()
    description "Basic operations in Bernstein basis";
	option package;
	global BernsteinBasis, `diff/BernsteinBasis`;
	export int;

	BernsteinBasis := proc(k, n, a, b, x)
		description "Bernstein basis polynomial";
		if k::numeric then
			if k < 0 then 
				return 0;
			end if
		end if;
		if n::numeric then
			if n < 0 then 
				return 0; 
			end if;
			if k::numeric then
				if k > n then
					return 0;
				end if;
			end if;
		end if;
		'procname'(_passed)
	end proc;

	`diff/BernsteinBasis` := proc()
		description "Derivative of the Bernstein basis polynomial in the Bernstein basis";
		if _npassed = 6 then
			if _passed[-1] = _passed[-2] then
				_passed[2] * BernsteinBasis(_passed[1] - 1, _passed[2] - 1, _passed[3], _passed[4], _passed[5]) / (_passed[4] - _passed[3]) -
				_passed[2] * BernsteinBasis(_passed[1], _passed[2] - 1, _passed[3], _passed[4], _passed[5]) / (_passed[4] - _passed[3]);
			end if;
		end if;
	end proc;
	
	int := proc()
		description "Integral of the Bernstein basis polynomial in the Bernstein basis";
		if type(_passed[1], 'specfunc'(anything, BernsteinBasis)) then
		    print("Will be implemented here...");
		end if;
		:-int(_passed)
	end proc;

end module;

Download bernstein.mw

In my code, without knowing what the expression is, other than it has RootOf, the code called allvalues and got internal error 

Error, (in SolveTools:-Basis) invalid input: igcd received 5/7, which is not valid for its 2nd argument

Is this to be expected depending on the input, or is this some internal problem I need to report?

restart;
expr:=RootOf(R^4*b+R^2*a*_Z+2*_Z^2-exp(RootOf(tanh(1/2*(a^2-8*b)^(1/2)*(4*S-_Z)/a)^2*R^4*a^2-8*tanh(1/2*(a^2-8*b)^(1/2)*(4*S-_Z)/a)^2*R^4*b-R^4*a^2+8*R^4*b-8*exp(_Z))))

allvalues(expr)

Error, (in SolveTools:-Basis) invalid input: igcd received 5/7, which is not valid for its 2nd argument

Maple 2023.2 on windows 10

ps.  Reported to Maplesoft

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