Unanswered Questions

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Hello,

In my model, it seems that I have parameters which are not evaluated.

Indeed, I'm not sure that the parameters defined with relations as you can see in the printscreen are evaluated.

 

One point which helps me to debug my model is to follow the evaluation of the construction of my model with the 3D visualization.

Questions :
1) How can I do to be sure that my parameters are evaluated ?

2) Is it possible to launch the update of the 3D visualization even if I still have some bugs in my model ?

Thank you for help.

Hello,

In my model, in order to better follow a analytical study, i would like to make some calculations with my paramters.

For example, I have defined :

xa=1

ya=2

R=sqrt(xa²+ya²)

I would define R in the parameters area so as to use it for some definitions in the definition of body (i use especially maplesim for multibody systems.)

How is it possible to define parameters thanks to relations ?

Here is my code & the error mesage.  What's wrong?

 

with(Statistics);
X := Vector*([0, 5, 10, 15, 20, 25, 30], datatype = float);
Y := Vector*([38.8, 53.8, 82.4, 107.6, 130.7, 152.4, 173.2], datatype = float);
NonlinearFit(av^2+bv+c, X, Y, v);
Error, (in Statistics:-NonlinearFit) invalid input: PostProcessData expects its 1st argument, x, to be of type {array, list, rtable}, but received w

I am trying to take out the intersection between two bases from one of the original basis. I have two matrices (A and B) and want to find the intesection between the range (or column space) of A and the null space of B. The range of A is 

X1:=ColumnSpace(A)

For some reason, the column space is not presented as a list, but with square brakes, so I convert this into a list of vectors:

X2:=SumBasis([X1[1],X1[2]])    %If I use the command Basis, it returns again square brakets, not sure why... 

The null space of B

X3:=NullSpace(B) 

X4:=IntersectionBasis([X2,X3])

X5:= X2\cap X4 % I am using latex code for the intersection symbol...

The result is the empty set! Evidently, X2 and X3 are differnt bases.

Any help would be really welcome! Many thanks!

Joaquin

let A be a matrix=

 

[  7        7      9    -17

   6        6      1    -2

 -12    -12    -27    1

   7       7      17   -15 ]

What is the reduced row echelon form of A?

What is the rank of A?

cilrcle.mw

i want to plot a circle with that centered at (0,0),and the radius is the length of Point2 and orgin

but it shows the error

how could i do to solve this

 

 

 

 

 

 

 

 

How to make Decimal number in maple by default? 

How to make radian to degrees? Think It is like this "degcos" but I cant see the correct result, because it is not showed in decimals

Why do I have to active all my varibles when I open the document after I have saved it?

 

Regards

Østerbro

Dear.All

 

I'm a beginner of Maple 13. 

 

In MATLAB, there is a command 'sigmaplot' which draw the 'SINGULAR VALUE OF SYSTEM H(jw)' over all frequency range. 

I want to obtain the function of the 'sigmaplot' graph about frequency variable 'w'.

 

so I defined matrix A,B,C,D in Maple13. 

 

and specify H like following

 

H:= Multiply(C,Multiply(Inversematrix(s*IdentityMatrix(8)-A),B))+D              

 

          --> It is to express H=C*((sI-A)^-1)*B+D that is the state-space matrix of frequency domain form.

 

and Maple 13 gave me a very long formular expressed by 's'.

 

Then I try to 'SingularValues' command 

 

but there came up 'Error Message : Error. (in content/polynom) general case of floats not handled'

 

I couldn't resolve this problem.... 

 

So I'm requesting your advice like this.

 

Could you give some advice ? 

 

I wnat to print the polar that contain a part of loops,but it always contains all loops.

how do I solve this preblem?

Any one can help me,please?

 

 

 

 

Hello everyone!

I'm working with Maple for 8 years and this is the first time I encounter such a problem:

I solve a linear ODE system for my quantum Mechanics research and i want to calculate a quantity formed by the solutions of the system. Everything is going fine with laplace transformation and the symbolic answer is very fast although extremely big (it uses RootOf simplification)

When i use evalf to take numerical approximations of the quantity, the answer is very fast. OK

When i leave unspecified two parameters in order to get a 3d plot the answer takes about 40mins to appear. I think it is too slow but anyway, i can live with it. OK

I want this 3d plot for different parameters of the ODE so i have to do the above process many times. But for some parameter values of the ODE, i get a 3dplot for which:

1) The display of numpoints (surface and line) is incorrect.

2) Plot gets deformed as long as i rotate it!!! The orientation angle changes the appearance of the plot, something obviously unacceptable. I have access to maple 17, 15, 14, and 12. Maple 17 and 15 exhibit this behavior (64 bit Maple editions). But when i tried with Maple 12-standard interface(64 bit) and Maple 14 -Classical interface (32bit) everything went fine, but at the cost of  300 extra secs. I got a solid 3d-plot that is invariant under rotations.

My video card is Ati radeon 6800 HD and i installed the latest drivers. I don't know why is this happening. I thought of putting the blame on me, but in maple 12 and maple 14 everything is fine. It is a pity, because Maple 17 gives very nice and smooth 3d plots.

The first plot is the correct one with maple 12. The second is produced with maple 14. All good.

The third and the second are produced with different orientations of the same plot (Maple 17). Wrong display of data and change of image after rotation. The final one is again from Maple 17 but with style=points. It is in is in full agreement with the first two plots. 

Conclusion: Style=surface and line doesnt produce the correct plot, while style=point does. As for hardware acceleration, i unticked it with no results.

Extra information: When i try to open the maple 12 worksheet which is correct, with Maple 17, again i take the wrong displayed and unstable picture. Moreover only maple 14 classical edition works well. Maple 14 standard interface is also pathological.

Heeeeelp guys!!!

 

 

Hi all,

 

I try  to plot phase portrait the below DAEs, 

diff(S(t), t)=-β*(1+δ*sin2Πt)*S(t)*I(t)-μ*S(t)+μ,

diff(I(t), t)=β*(1+δ*sin2Πt)*S(t)*I(t)-γ*I(t)-μ*I(t),

0=S(t)+I(t)+R(t)-1.

where

μ=0.01,

β=1510,

δ=0.02,

γ=50,

I really appreciate your help.

hi

 

please help me :

 

 

restart; eq := diff(T(x, y), x) = a*(diff(T(x, y), `$`(y, 2)))/u(y); u := proc (y) options operator, arrow; (-1)*1.218493440*10^11*y^2+4.244913600*10^6*y+0.33e-1 end proc; eq; ICs := (D[1](T))(x, 0) = 1000, (D[1](T))(x, 0.25e-4) = 2000, T(0, y) = 0; T_sol := pdsolve({ICs, eq}, T(x, y)); T_sol

diff(T(x, y), x) = a*(diff(diff(T(x, y), y), y))/u(y)

 

proc (y) options operator, arrow; (-1)*1.218493440*100000000000*(y^2)+4.244913600*1000000*y+0.33e-1 end proc

 

diff(T(x, y), x) = a*(diff(diff(T(x, y), y), y))/(-0.1218493440e12*y^2+4244913.600*y+0.33e-1)

 

(D[1](T))(x, 0) = 1000, (D[1](T))(x, 0.25e-4) = 2000, T(0, y) = 0

 

Error, (in PDEtools:-Library:-NormalizeBoundaryConditions) unable to isolate the functions {T(0, y), (D[1](T))(x, 0), (D[1](T))(x, 0.25e-4)} in the given boundary conditions {T(0, y) = 0, (D[1](T))(x, 0) = 1000, (D[1](T))(x, 0.25e-4) = 2000}

 

T_sol

(1)

NULL

``

BC1 = diff(T(x, 0), y)=1000

BC2 = diff(T(x, 0.000025), y)=2000

IC = T(0,y)=0

where :

u(y)=-1.218493440*10^11*y^2+4.244913600*10^6*y+0.033

Download PDE_Sol.mw

Hi,

 

  I have a loop code, such as

 

****

i_max:=10;

for i from 1 to i_max do
  blah blah blah

end do;

****

 

  I would like to clean memory, something like restart suppose to do, after each cycle. Restart could only work at top level. How should I do to clean memory after each cycle?

 

Dear all,

It's very convenient to define a DE or PDE through Differential Operator D, for example,

((D[1, 1]+D[1, 2]+D[2, 2])(z))(x, y) = exp(x)*sin(y)

Is it possible to realize Inverse Operator Method of Operator D? How to solve the following equation if we rewrite the pde through inverse operator method?

(z)(x, y)=((D[1, 1]+D[1, 2]+D[2, 2])^(-1))exp(x)*sin(y)

 

Thanks a lot.

 

We are using your maple service and required your help in solving below problem '
1. Create a question type Maple Numeric with correct answer 27
2. If user gives 27d and 27e and on evaluate with your service getting response as true.

Please find the attached screens for more information. Also see request and response for numeric value 10 and if you see response even 10d is evaluating as true. This is wrong, please review and advice.

-------------------

mapleScript :: before substitution

expr1:="<math><cn>${#answer}</cn></math>"; expr2:="<math><cn>${#correctAnswer}</cn></math>"; expr3:="<math><cn>${#tolrence}</cn></math>";expr1 := StringTools[SubstituteAll](expr1, ",", "");expr1 := StringTools[RegSubs]("<apply>< *([a-zA-Z]+)[ /]*>" = "<apply><ci>\1</ci>", expr1);expr1 := StringTools[RegSubs]("<apply><ci>(plus|minus|divide|times|power)</ci>" = "<apply><\\1/>", expr1);expr1 := StringTools[RegSubs]("<apply><ci> *([a-zA-Z]+) *</ci>" = "<apply><ci>x_\\1</ci>", expr1);expr1 := StringTools[RegSubs]("<c[ni]> *([0-9]+\\.[0-9]+) *</c[ni]>" = "<apply><ci>convert</ci><cn>\\1</cn><ci>rational</ci><ci>exact</ci></apply>", expr1);expr2 := StringTools[SubstituteAll](expr2, ",", "");expr2 := StringTools[RegSubs]("<apply>< *([a-zA-Z]+)[ /]*>" = "<apply><ci>\\1</ci>", expr2);expr2 := StringTools[RegSubs]("<apply><ci>(plus|minus|divide|times|power)</ci>" = "<apply><\\1/>", expr2);expr2 := StringTools[RegSubs]("<apply><ci> *([a-zA-Z]+) *</ci>" = "<apply><ci>x_\\1</ci>", expr2);expr2 := StringTools[RegSubs]("<c[ni]> *([0-9]+\\.[0-9]+) *</c[ni]>" = "<apply><ci>convert</ci><cn>\\1</cn><ci>rational</ci><ci>exact</ci></apply>", expr2);expr1 := MathML[ImportContent](expr1);expr2 := MathML[ImportContent](expr2);expr := combine(expr1-expr2, [radical,power,trig,ln,power,radical], symbolic);expr3:=MathML[ImportContent](expr3);result := evalb(abs(simplify(expr, symbolic))<=expr3);result := evalb(result = true);if not result then result := evalb(abs(simplify(expr, assume = real))<=expr3) end if;result := evalb(result = true);

mapleScript :: (user input) 10d

expr1:="<math><cn>10d</cn></math>"; expr2:="<math><cn>10</cn></math>"; expr3:="<math><cn>0</cn></math>";expr1 := StringTools[SubstituteAll](expr1, ",", "");expr1 := StringTools[RegSubs]("<apply>< *([a-zA-Z]+)[ /]*>" = "<apply><ci>\1</ci>", expr1);expr1 := StringTools[RegSubs]("<apply><ci>(plus|minus|divide|times|power)</ci>" = "<apply><\\1/>", expr1);expr1 := StringTools[RegSubs]("<apply><ci> *([a-zA-Z]+) *</ci>" = "<apply><ci>x_\\1</ci>", expr1);expr1 := StringTools[RegSubs]("<c[ni]> *([0-9]+\\.[0-9]+) *</c[ni]>" = "<apply><ci>convert</ci><cn>\\1</cn><ci>rational</ci><ci>exact</ci></apply>", expr1);expr2 := StringTools[SubstituteAll](expr2, ",", "");expr2 := StringTools[RegSubs]("<apply>< *([a-zA-Z]+)[ /]*>" = "<apply><ci>\\1</ci>", expr2);expr2 := StringTools[RegSubs]("<apply><ci>(plus|minus|divide|times|power)</ci>" = "<apply><\\1/>", expr2);expr2 := StringTools[RegSubs]("<apply><ci> *([a-zA-Z]+) *</ci>" = "<apply><ci>x_\\1</ci>", expr2);expr2 := StringTools[RegSubs]("<c[ni]> *([0-9]+\\.[0-9]+) *</c[ni]>" = "<apply><ci>convert</ci><cn>\\1</cn><ci>rational</ci><ci>exact</ci></apply>", expr2);expr1 := MathML[ImportContent](expr1);expr2 := MathML[ImportContent](expr2);expr := combine(expr1-expr2, [radical,power,trig,ln,power,radical], symbolic);expr3:=MathML[ImportContent](expr3);result := evalb(abs(simplify(expr, symbolic))<=expr3);result := evalb(result = true);if not result then result := evalb(abs(simplify(expr, assume = real))<=expr3) end if;result := evalb(result = true);

evalResult ::
expr1 := "<math><cn>10d</cn></math>" expr2 := "<math><cn>10</cn></math>" expr3 := "<math><cn>0</cn></math>" expr1 := "<math><cn>10d</cn></math>" expr1 := "<math><cn>10d</cn></math>" expr1 := "<math><cn>10d</cn></math>" expr1 := "<math><cn>10d</cn></math>" expr1 := "<math><cn>10d</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr1 := 10. expr2 := 10 expr := 0. expr3 := 0 result := true result := true result := true

mapleScript :: (user input) 10
expr1:="<math><cn>10</cn></math>"; expr2:="<math><cn>10</cn></math>"; expr3:="<math><cn>0</cn></math>";expr1 := StringTools[SubstituteAll](expr1, ",", "");expr1 := StringTools[RegSubs]("<apply>< *([a-zA-Z]+)[ /]*>" = "<apply><ci>\1</ci>", expr1);expr1 := StringTools[RegSubs]("<apply><ci>(plus|minus|divide|times|power)</ci>" = "<apply><\\1/>", expr1);expr1 := StringTools[RegSubs]("<apply><ci> *([a-zA-Z]+) *</ci>" = "<apply><ci>x_\\1</ci>", expr1);expr1 := StringTools[RegSubs]("<c[ni]> *([0-9]+\\.[0-9]+) *</c[ni]>" = "<apply><ci>convert</ci><cn>\\1</cn><ci>rational</ci><ci>exact</ci></apply>", expr1);expr2 := StringTools[SubstituteAll](expr2, ",", "");expr2 := StringTools[RegSubs]("<apply>< *([a-zA-Z]+)[ /]*>" = "<apply><ci>\\1</ci>", expr2);expr2 := StringTools[RegSubs]("<apply><ci>(plus|minus|divide|times|power)</ci>" = "<apply><\\1/>", expr2);expr2 := StringTools[RegSubs]("<apply><ci> *([a-zA-Z]+) *</ci>" = "<apply><ci>x_\\1</ci>", expr2);expr2 := StringTools[RegSubs]("<c[ni]> *([0-9]+\\.[0-9]+) *</c[ni]>" = "<apply><ci>convert</ci><cn>\\1</cn><ci>rational</ci><ci>exact</ci></apply>", expr2);expr1 := MathML[ImportContent](expr1);expr2 := MathML[ImportContent](expr2);expr := combine(expr1-expr2, [radical,power,trig,ln,power,radical], symbolic);expr3:=MathML[ImportContent](expr3);result := evalb(abs(simplify(expr, symbolic))<=expr3);result := evalb(result = true);if not result then result := evalb(abs(simplify(expr, assume = real))<=expr3) end if;result := evalb(result = true);

evalResult ::
expr1 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr3 := "<math><cn>0</cn></math>" expr1 := "<math><cn>10</cn></math>" expr1 := "<math><cn>10</cn></math>" expr1 := "<math><cn>10</cn></math>" expr1 := "<math><cn>10</cn></math>" expr1 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr2 := "<math><cn>10</cn></math>" expr1 := 10 expr2 := 10 expr := 0 expr3 := 0 result := true result := true result := true
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