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sand15

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Cannot be reproduced...

sand15 1369
November 16 2025
0 0

No problems using Maple 2015 (and I guess newer versions) if things are written properly.
Do you use a legal Maple version? If yes which one ?
A good start would be to ubload your mw file using the big green up-arrow in the menubar.

Worksheet Mode: No_NULL_issues.mw

Document Mode: No_NULL_issues_2.mw

Maybe this comment is stupid but......

sand15 1369
November 16 2025
0 0

... did you try using the dethlimit option as adviced in the error message?

solution := Optimization:-LPSolve(
  C_max
  , constraints
  , assume = nonnegative
  , integervariables = binary_vars
  , variables = Vars
  , depthlimit = 300  # for instance
):

# or, to get some info about the time and memory used

solution := CodeTools:-Usage(
  Optimization:-LPSolve(
    C_max
    , constraints
    , assume = nonnegative
    , integervariables = binary_vars
    , variables = Vars
    , depthlimit = 300
  )
):

@Math-dashti What does this paper h...

sand15 1369
November 16 2025
0 0

@Math-dashti 

What does this paper have to do with your original question?

Question...

sand15 1369
November 16 2025
0 0

What are the ranges for epsilon, u0 and v0 (those you want to investigate, not those you coded) ?

Non convergence...

sand15 1369
November 15 2025
0 0

@KIRAN SAJJAN 

Non convergence appears when yu < yl, which depends on the values of x and t.

This can be shown in a very simple way.
Thus, for instance when tfixed = 1 dsolve does not converge over the range xfixed = 0..2 , but only over the subrange xfixed = 0.366825212..1.633174787.

Read the attached file carefully and try to figure out what you can do with it XT_non_convergence_issue.mw

No its not converging...

sand15 1369
November 15 2025
0 0

@KIRAN SAJJAN 

You asked for a plot in the range x=0..600.
In your last wotksheet you took x=5 and claim "it's converging"... yes indeed, for this value of x.

Now take x=6 and tell me if "it's converging".

Not sure...

sand15 1369
November 15 2025
0 0

@KIRAN SAJJAN 

you understood what I said when I told you to try and fix yourself the "Newton non converging" issue

Please...

sand15 1369
November 15 2025
0 0

Upload your worksheet by using the big green up-arrow in the menubar

All has been deleted...

sand15 1369
November 14 2025
0 0

@Math-dashti 

Have you given up on this question, or is it still of interest to you?

Is it you who deleted your last question...

sand15 1369
November 14 2025
0 0

Is it you who deleted your last question, which I spent the time to answer?

If that's the case, let me tell you that you are being particularly impolite and scornful. 

For the record your question was


To which I answered

I update my answer...

sand15 1369
November 14 2025
0 0

@Math-dashti 

look at it

Is this you are looking for?...

sand15 1369
November 13 2025
0 0

@Math-dashti 

> 

restart; with(plots); f := proc (u, v) options operator, arrow; v*(2*chi*u^2+p) end proc; g := proc (u, v) options operator, arrow; -beta[2]*u^5-2*chi*u*v^2+u*p*k^2-beta[1]*u^3+u*w end proc; equilibria := solve({f(u, v) = 0, g(u, v) = 0}, {u, v}, explicit)
> 

# Find the parameters in f(u, và and g(u, v)

indE := convert( indets({f(u, v) = 0, g(u, v) = 0}, name) minus {u, v}, list)

[chi, k, p, w, beta[1], beta[2]]

 (1)
> 

# Define a function 'Equilibria" whch maps 'indE' to 'equilibria'

Equilibria := unapply({equilibria}, indE):
> 

# Example of use: a change of name

Equilibria(X, k, p, alpha[1], alpha[2], alpha[3])

{{u = 0, v = 0}, {u = -(1/2)*(-(2*alpha[2]+2*(4*k^2*p*alpha[3]+4*alpha[1]*alpha[3]+alpha[2]^2)^(1/2))/alpha[3])^(1/2), v = 0}, {u = (1/2)*(-(2*alpha[2]+2*(4*k^2*p*alpha[3]+4*alpha[1]*alpha[3]+alpha[2]^2)^(1/2))/alpha[3])^(1/2), v = 0}, {u = -(1/2)*2^(1/2)*((-alpha[2]+(4*k^2*p*alpha[3]+4*alpha[1]*alpha[3]+alpha[2]^2)^(1/2))/alpha[3])^(1/2), v = 0}, {u = (1/2)*2^(1/2)*((-alpha[2]+(4*k^2*p*alpha[3]+4*alpha[1]*alpha[3]+alpha[2]^2)^(1/2))/alpha[3])^(1/2), v = 0}, {u = -(1/2)*(-2*X*p)^(1/2)/X, v = -(1/4)*2^(1/2)*(X*(4*X^2*k^2*p+4*X^2*alpha[1]+2*X*p*alpha[2]-p^2*alpha[3]))^(1/2)/X^2}, {u = -(1/2)*(-2*X*p)^(1/2)/X, v = (1/4)*2^(1/2)*(X*(4*X^2*k^2*p+4*X^2*alpha[1]+2*X*p*alpha[2]-p^2*alpha[3]))^(1/2)/X^2}, {u = (1/2)*(-2*X*p)^(1/2)/X, v = -(1/4)*2^(1/2)*(X*(4*X^2*k^2*p+4*X^2*alpha[1]+2*X*p*alpha[2]-p^2*alpha[3]))^(1/2)/X^2}, {u = (1/2)*(-2*X*p)^(1/2)/X, v = (1/4)*2^(1/2)*(X*(4*X^2*k^2*p+4*X^2*alpha[1]+2*X*p*alpha[2]-p^2*alpha[3]))^(1/2)/X^2}}

 (2)
> 

# Example of use: some parameters are numeric

Equilibria(chi, k, p, 1, 3/5, -7)

{{u = 0, v = 0}, {u = -(1/2)*(6/35+(2/7)*(-28*k^2*p-691/25)^(1/2))^(1/2), v = 0}, {u = (1/2)*(6/35+(2/7)*(-28*k^2*p-691/25)^(1/2))^(1/2), v = 0}, {u = -(1/2)*2^(1/2)*(3/35-(1/7)*(-28*k^2*p-691/25)^(1/2))^(1/2), v = 0}, {u = (1/2)*2^(1/2)*(3/35-(1/7)*(-28*k^2*p-691/25)^(1/2))^(1/2), v = 0}, {u = -(1/2)*(-2*chi*p)^(1/2)/chi, v = -(1/4)*2^(1/2)*(chi*(4*chi^2*k^2*p+(6/5)*chi*p+7*p^2+4*chi^2))^(1/2)/chi^2}, {u = -(1/2)*(-2*chi*p)^(1/2)/chi, v = (1/4)*2^(1/2)*(chi*(4*chi^2*k^2*p+(6/5)*chi*p+7*p^2+4*chi^2))^(1/2)/chi^2}, {u = (1/2)*(-2*chi*p)^(1/2)/chi, v = -(1/4)*2^(1/2)*(chi*(4*chi^2*k^2*p+(6/5)*chi*p+7*p^2+4*chi^2))^(1/2)/chi^2}, {u = (1/2)*(-2*chi*p)^(1/2)/chi, v = (1/4)*2^(1/2)*(chi*(4*chi^2*k^2*p+(6/5)*chi*p+7*p^2+4*chi^2))^(1/2)/chi^2}}

 (3)
 

 

Download Is_this_you_are_looking_for.mw

?...

sand15 1369
November 13 2025
0 0

@Math-dashti 

I'm not sure I trully understand what you are saying.
Read carefully this worksheet and let me know if it answers your problem simpler_sand15.mw

No problem...

sand15 1369
November 12 2025
0 0

with Maple 2015, worksheet mode , input display = Maple Notation, output display = 2-D Math Notation

> 

restart
> 

kernelopts(version)

`Maple 2015.2, APPLE UNIVERSAL OSX, Dec 20 2015, Build ID 1097895`

 (1)
> 

with(Units):
> 

d := 10*Unit('cm');
c__w := 0.47;
F__luft := 0.040146*Unit('N');

10*Units:-Unit('cm')

  

.47

  

0.40146e-1*Units:-Unit('N')

 (2)
> 

F__luft = 1/2*rho__luft*A*c__w*v^2;

0.40146e-1*Units:-Unit('N') = .2350000000*rho__luft*A*v^2

 (3)
> 

A := Pi*(d/2)^2

25*Pi*Units:-Unit('cm')^2

 (4)
> 

rho__luft := 1.2*Unit('kg/m^3')

1.2*Units:-Unit(('kg')/('m')^3)

 (5)
> 

under_radical := 2*F__luft/(rho__luft*A*c__w);

under_radical := simplify(under_radical);
 

0.1812605488e-2*Units:-Unit('N')/(Units:-Unit(('kg')/('m')^3)*Units:-Unit('cm')^2)

  

18.12605488*Units:-Unit(('m')^2/('s')^2)

 (6)
> 

v = simplify(surd(under_radical, 2))

v = 4.257470479*Units:-Unit(('m')/('s'))

 (7)
 

 

Download No_problem_with_Maple_2015.mw
 

> 

restart
> 

kernelopts(version)

`Maple 2015.2, APPLE UNIVERSAL OSX, Dec 20 2015, Build ID 1097895`

 (1)
> 

with(Units):
> 

d := 10*Unit('cm');
c__w := 0.47;
F__luft := 0.040146*Unit('N');

10*Units:-Unit('cm')

  

.47

  

0.40146e-1*Units:-Unit('N')

 (2)
> 

F__luft = 1/2*rho__luft*A*c__w*v^2;

0.40146e-1*Units:-Unit('N') = .2350000000*rho__luft*A*v^2

 (3)
> 

A := Pi*(d/2)^2

25*Pi*Units:-Unit('cm')^2

 (4)
> 

rho__luft := 1.2*Unit('kg/m^3')

1.2*Units:-Unit(('kg')/('m')^3)

 (5)
> 

under_radical := 2*F__luft/(rho__luft*A*c__w);

under_radical := simplify(under_radical);
 

0.1812605488e-2*Units:-Unit('N')/(Units:-Unit(('kg')/('m')^3)*Units:-Unit('cm')^2)

  

18.12605488*Units:-Unit(('m')^2/('s')^2)

 (6)
> 

v = simplify(surd(under_radical, 2))

v = 4.257470479*Units:-Unit(('m')/('s'))

 (7)
 

 

Download No_problem_with_Maple_2015.mw

Adjust scales...

sand15 1369
November 12 2025
0 0

@Andiguys 

The things you will have to adjust for future data are pink written in the attached file Scalling_issue_fixsd.mw
.

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