nm

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13 years, 34 days

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These are questions asked by nm

Is there a command or method in Maple to list all initially protected names?

This page https://www.maplesoft.com/support/help/Maple/view.aspx?path=UndocumentedNames list undocumented protected names, and this page https://www.maplesoft.com/support/help/Maple/view.aspx?path=initialconstants  lists initially known names, which I assume are all protected.

But what about a list of all protected names? sin,cos, eval, uneval, etc.. any name that can't be assigned to. In my search so far, I could not find how to find these names. There are 100's of such names. Can one get them all in a list to look at?

Using Maple 2019.1

Could someone confirm if this is a problem in this sample application?

In 2019, in the folder 

    C:\Program Files\Maple 2019\samples\ProgrammingGuide\RandomnessTests

There is sample application. Opening the main module file RandomnessTests.mpl  and scrolling down a little bit to the include statements show

$include "WaldWolfowitz.mm"
$include "BitFrequency.mm"
$include "SequenceFrequency.mm"
$include "Compressibility.mm"
$include "BinaryRank.mm"
$include "Entropy.mm"

$include "Data.mm"
$include "Visualization.mm"

However, in the same folder, there is no Data.mm file. There is only Data.mpl file.

So how could this sample application work?  

This sample app have more problems. The file Visualization.mm  say

Data := module()
option package;
...

And the file Data.mpl has

Data := module()
....

This is all so confusing. Seems someone made some typos and not tested this app? Why put a sample application which makes learning packages in Maple more confusing?

ps. I did not yet try to figure how to locad it and run it myself, I was just browsing it.

 

 

I spend some time searching and reading help. But not able to find if this is possible.

I use worksheet only (i.e. not 2D document). I have my display set as

 

I'd like diff(y(x),x) to display as y'(x) in output.

I know I can do this 

PDEtools:-declare(y(x), prime = x);

And that will make diff(y(x),x) display as y'  but I want y'(x). And the same for diff(y(x),x$2) to display as y''(x). And to be clear, y(x) will still display as y(x).  I am mainly interested in making the derivative display a little nicer if possible.

Is there a way to do this?

I am using 2019.1 on windows 10.

 

In answers given in 

In https://www.mapleprimes.com/questions/227546-How-To-Make-Odetest-Verify-Dsolve

It shows that odetest() did not verify a solution to ODE becuase solution was using hypergeom special functions. If the solution to the ODE was in integral form, then odetest() will verify it OK.

But what to do if the solution I want to verify is already in hypergoem? If I try odetest() it will fail to verify now. Then I can try to convert the solution to integral form and try again.

But when  using convert(sol,Int) followed by odetest() it did not work.

The solutions I try to verify are hand solutions or book solutions, and not coming from dsolve. 

But some of them are the same solution that comes from dsolve() when not using the useInt option. 

Also, I am doing this all inside a Maple program. It is not an interactive process. So I can't do plots and look at them to decide on anything. So verification must all be implemented in code.

The question is: Why did convert(hand_solution,Int) not give the same result as dsolve(ode,useInt)? Is there another way around this? (May be I am asking for too much in this one based on answers in the above link, So that is OK if not possible. But I really like the solution given when using "useInt" option. Much more clear than otherwise).
 

restart;

ode := diff(y(x), x)*(x^3 + 1)^(2/3) + (1 + y(x)^3)^(2/3) = 0;
sol_int:=dsolve(ode,useInt);
odetest(sol_int,ode); #OK now, since solution in integral form

(diff(y(x), x))*(x^3+1)^(2/3)+(1+y(x)^3)^(2/3) = 0

Int(1/(x^3+1)^(2/3), x)+Intat(1/(_a^3+1)^(2/3), _a = y(x))+_C1 = 0

0

hand_solution:= x*hypergeom([1/3, 2/3], [4/3], -x^3) + y(x)*hypergeom([1/3, 2/3], [4/3], -y(x)^3) + _C1 = 0;
convert(hand_solution,Int); #Why this did not give same result as ABOVE?

x*hypergeom([1/3, 2/3], [4/3], -x^3)+y(x)*hypergeom([1/3, 2/3], [4/3], -y(x)^3)+_C1 = 0

(2/9)*x*Pi*3^(1/2)*(Int(1/(_t1^(1/3)*(1-_t1)^(1/3)*(x^3*_t1+1)^(1/3)), _t1 = 0 .. 1))/GAMMA(2/3)^3+(2/9)*y(x)*Pi*3^(1/2)*(Int(1/(_t1^(1/3)*(1-_t1)^(1/3)*(y(x)^3*_t1+1)^(1/3)), _t1 = 0 .. 1))/GAMMA(2/3)^3+_C1 = 0

odetest(%,ode); #does not give zero

-y(x)^3*(1+y(x)^3)^(2/3)*(Int(_t1^(2/3)/((1-_t1)^(1/3)*(y(x)^3*_t1+1)^(4/3)), _t1 = 0 .. 1))+(x^3+1)^(2/3)*(Int(_t1^(2/3)/((1-_t1)^(1/3)*(x^3*_t1+1)^(4/3)), _t1 = 0 .. 1))*x^3-(x^3+1)^(2/3)*(Int(1/(_t1^(1/3)*(1-_t1)^(1/3)*(x^3*_t1+1)^(1/3)), _t1 = 0 .. 1))+(1+y(x)^3)^(2/3)*(Int(1/(_t1^(1/3)*(1-_t1)^(1/3)*(y(x)^3*_t1+1)^(1/3)), _t1 = 0 .. 1))

 

 

Maple 2019.1

Download 072619_2.mw

 

 

 

THis is another ode which I am not able to get odetest to give zero. Any one knows of a trick to verify this solution? It might be just that the solution is too complicated for odetest to verify?


 

restart;

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

(diff(y(x), x))*(x^3+1)^(2/3)+(1+y(x)^3)^(2/3) = 0

x*hypergeom([1/3, 2/3], [4/3], -x^3)+y(x)*hypergeom([1/3, 2/3], [4/3], -y(x)^3)+_C1 = 0

odetest(sol,ode);

-9*(1+y(x)^3)^(1/3)*(x^3+1)^(2/3)*hypergeom([4/3, 5/3], [7/3], -x^3)*x^3*GAMMA(2/3)*(-y(x)^3)^(1/6)/(9*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*y(x)^3*(-y(x)^3)^(1/6)*(1+y(x)^3)^(1/3)*GAMMA(2/3)-4*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -y(x)^3/(1+y(x)^3)+1/(1+y(x)^3)))+9*y(x)^6*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*GAMMA(2/3)*(-y(x)^3)^(1/6)/(9*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*y(x)^3*(-y(x)^3)^(1/6)*(1+y(x)^3)^(1/3)*GAMMA(2/3)-4*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -y(x)^3/(1+y(x)^3)+1/(1+y(x)^3)))+9*y(x)^3*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*GAMMA(2/3)*(-y(x)^3)^(1/6)/(9*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*y(x)^3*(-y(x)^3)^(1/6)*(1+y(x)^3)^(1/3)*GAMMA(2/3)-4*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -y(x)^3/(1+y(x)^3)+1/(1+y(x)^3)))-4*(1+y(x)^3)^(2/3)*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -(y(x)^3-1)/(1+y(x)^3))/(9*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*y(x)^3*(-y(x)^3)^(1/6)*(1+y(x)^3)^(1/3)*GAMMA(2/3)-4*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -y(x)^3/(1+y(x)^3)+1/(1+y(x)^3)))+4*(1+y(x)^3)^(1/3)*(x^3+1)^(1/3)*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -(x^3-1)/(x^3+1))*(-y(x)^3)^(1/6)/((-x^3)^(1/6)*(9*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*y(x)^3*(-y(x)^3)^(1/6)*(1+y(x)^3)^(1/3)*GAMMA(2/3)-4*Pi*3^(1/2)*LegendreP(-1/3, -1/3, -y(x)^3/(1+y(x)^3)+1/(1+y(x)^3))))

simplify(%);

-9*((4/9)*(1+y(x)^3)^(2/3)*Pi*3^(1/2)*LegendreP(-1/3, -1/3, (-y(x)^3+1)/(1+y(x)^3))*(-x^3)^(1/6)+(-(4/9)*(1+y(x)^3)^(1/3)*(x^3+1)^(1/3)*Pi*3^(1/2)*LegendreP(-1/3, -1/3, (-x^3+1)/(x^3+1))+(-x^3)^(1/6)*((-y(x)^6-y(x)^3)*hypergeom([4/3, 5/3], [7/3], -y(x)^3)+x^3*(1+y(x)^3)^(1/3)*hypergeom([4/3, 5/3], [7/3], -x^3)*(x^3+1)^(2/3))*GAMMA(2/3))*(-y(x)^3)^(1/6))/((-x^3)^(1/6)*(9*hypergeom([4/3, 5/3], [7/3], -y(x)^3)*y(x)^3*(-y(x)^3)^(1/6)*(1+y(x)^3)^(1/3)*GAMMA(2/3)-4*Pi*3^(1/2)*LegendreP(-1/3, -1/3, (-y(x)^3+1)/(1+y(x)^3))))

 


 

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Maple 2019.1, Physics 395

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