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solarsysem.mw Sorry for the repost but this is my newest document.

I have to create a solar system model on maple by defining a force equation then using the seq function to create a diffeq and then solving those differential equations using the initial conditions with the sun at (0, 0, 0) in xyz coordinates.

It works until my last "ic1" entry and I get an error in dsolve/numeric/process_input

I'm pretty desperate, I'll appreciate any help I can get

 

 

 

 

I am a new user. I have a worksheet and need to see how the the procs are being accessed as it does not look like they are being called and executed as I would expect. What is the most efficient way to debug and see the calling order of my Procs?

 

Thanks in advance,

Bonnie

Hi, 

I am a college student that is aspiring to become a theoretical theorist. I have postulates that are not in mathematical form yet, and I would like to use a program that can help with this process. I am new to the usage of Maple products, and I have questions. Is it possible to use Maple in this way, before getting to the difficult calculus steps? Can MapleSim or Maple Physics, perform simulations, or models of physics calculations?

Thank you,

Roi

 

Wanting to edit a post of mine, I accidentally clicked the 'More'-button and chose 'Edit' on anothers post. I immediately saw that it was not my post, and did of course not alter it. But it left me somewhat shocked, for it would seem to imply that anyone can edit (and delete, as well, have just investigated that) anyones post(s). That I think is something that really needs to be remedied as soon as possible.

Here is my command and i will use to make the user interface.

Orginal:

for i to l do

for j from x to y do

block[i][j] := 1-block[i][j]

end do;

c_block[i] := block[i];

c_block[i] := parse(cat(c_block[i][]))

end do

Can someone help me to edit my command so that i can write it in Click Edit Action for a button? thank you.

Do(for i from 1 to %l do)
   Do(for j from x to y do)
      Do(block[i][j] = 1-block[i][j]); 
    end do);
   Do(c_block[i] := block[i]);
  Do( c_block[i] := parse(cat(c_block[i][])));
end do);

Hey

I have a very simple function and I need to plot it. The plot is however not smooth and there are annoying cuts and steps which don't go away no matter how I set the options. This problem has been puzzling me for a while and I really appreciate any help.

The followings are all the possible options I could find, none seems to work. You can take a look at this file: ploting_problem.mw

Thanks

I saw yesterday evening (at home) a very elegant answer to my question "Intersection of real intervals" .
Unfortunately I can't retrieve it this morning (I'm in the office)

It was something like  coulitbe('_x' ...) ... but I don't remember it entirely
I think it came from Carl Love or maybe Mac Dude

 Could you please send me it again ?

 

Thanks


Suppose I have a triplet a[5], a[6], a[7]and an expression given as below:

V[5]*a[5]+V[6]*a[6]+V[7]*a[7]+V[2]+V[9]

How I can list all possible forms of above expression for triplet "(a[5], a[6], a[7])->(a[5], a[6], a[7]), (a[5], a[6], 0), (a[5], 0, a[7]), (0, a[6], a[7]), (a[5], 0, 0), (0, a[6], 0 ), (0, 0, a[7]), (0, a[6], 0), (0, 0, 0) "etc


Download triplet.mw

Regards

Dear all

I need a help to compute the integral from -1 to 1 of product of derivative of legendre polynomial

> restart;
> with(orthopoly);

P(n, x); # Designe the legendre polynomial of degree n
I would like to compute

int(diff(P(n,x),x)*diff(P(m,x),x),x=-1..1) ;

 

In this previous formula when I put n=2 and m=3 I can get the result but in general  case i cannot,

Many thanks

 

 

Howdy all,

I am trying to create a solar system model by defining a force equation then using the sequence function to create a differential equation and then solving those differential equations using the initial conditions (in X,Y,Z coordinates). So far I have the code below.


m[1] = 1.989*10^30; m[2] = 3.301*10^23; m[3] = 4.867*10^24; m[4] = 5.972*10^24+7.346*10^22; m[5] = 6.417*10^23; m[6] = 1.899*10^27; m[7] = 5.685*10^26; m[8] = 8.682*10^25; m[9] = 1.024*10^26; m[10] = 1.471*10^22; m[11] = 9.3*10^20; m[12] = 2.6*10^20; m[13] = 2*10^20; m[14] = 8.67*10^19; m[15] = 3.9*10^19; mass := Matrix(15, 1, [1.989*10^30, 3.301*10^23, 4.867*10^24, 5.972*10^24+7.346*10^22, 6.417*10^23, 1.899*10^27, 5.685*10^26, 8.682*10^25, 1.024*10^26, 1.471*10^22, 9.3*10^20, 2.6*10^20, 2*10^20, 8.67*10^19, 3.9*10^19]); G := 6.67408*10^(-11)

mass := Vector(4, {(1) = ` 15 x 1 `*Matrix, (2) = `Data Type: `*anything, (3) = `Storage: `*rectangular, (4) = `Order: `*Fortran_order})

 

0.6674080000e-10

(1)

sqrt(sum(x[i](t)^2, i = 1 .. 3));

(x[1](t)^2+x[2](t)^2+x[3](t)^2)^(1/2)

 

proc (i, j) options operator, arrow; sqrt(sum((x[i, k](t)-x[j, k](t))^2, k = 1 .. 3)) end proc

 

((x[1, 1](t)-x[3, 1](t))^2+(x[1, 2](t)-x[3, 2](t))^2+(x[1, 3](t)-x[3, 3](t))^2)^(1/2)

 

proc (i, j) options operator, arrow; [x[j, 1](t)-x[i, 1](t), x[j, 2](t)-x[i, 2](t), x[j, 3](t)-x[i, 3](t)] end proc

 

[x[3, 1](t)-x[1, 1](t), x[3, 2](t)-x[1, 2](t), x[3, 3](t)-x[1, 3](t)]

 

x[3, 1](t)-x[1, 1](t)

 

x[j, 1](t)-x[i, 1](t), x[j, 2](t)-x[i, 2](t), x[j, 3](t)-x[i, 3](t)

 

proc (i, j) options operator, arrow; [seq(x[j, k](t)-x[i, k](t), k = 1 .. 3)] end proc

 

[x[3, 1](t)-x[1, 1](t), x[3, 2](t)-x[1, 2](t), x[3, 3](t)-x[1, 3](t)]

 

x[3, 1](t)-x[1, 1](t)

(2)

diff(x[0, 1](t), t, t) = force(0)[1]:

initialPositions := Matrix([[0, 0, 0], [-0.210e8, 0.426e8, 0.541e7], [0.106e9, -0.244e8, -0.644e7], [-0.139e9, -0.569e8, 0.316e4], [-0.177e9, -0.155e9, 0.111e7], [-0.802e9, 0.131e9, 0.174e8], [-0.480e9, -0.142e10, 0.438e8], [0.280e10, 0.103e10, -0.324e8], [0.420e10, -0.157e10, -0.645e8], [0.132e10, -0.477e10, 0.127e9], [0.431e9, -0.690e8, -0.816e8], [0.228e9, 0.305e9, -0.368e8], [0.300e9, -0.351e9, 0.217e9], [-0.434e9, -0.841e7, -0.284e8], [-0.115e9, -0.466e9, -0.612e8]])

initialPositions := Vector(4, {(1) = ` 15 x 3 `*Matrix, (2) = `Data Type: `*anything, (3) = `Storage: `*rectangular, (4) = `Order: `*Fortran_order})

(3)

initialVelocities := Matrix([[0, 0, 0], [-0.462e7, -0.170e7, 0.285e6], [0.666e6, 0.293e7, 0.183e4], [0.936e6, -0.239e7, 83.3], [0.145e7, -0.140e7, -0.650e5], [-0.196e6, -0.106e7, 0.879e4], [0.745e6, -0.271e6, -0.250e5], [-0.208e6, 0.524e6, 0.467e4], [0.161e6, 0.442e6, -0.129e5], [0.463e6, 0.294e5, -0.137e6], [0.193e6, 0.143e7, 0.923e4], [-0.119e7, 0.974e6, 0.116e6], [0.978e6, 0.562e6, -0.470e6], [0.166e6, -0.156e7, -0.131e5], [0.132e7, -0.170e6, 0.395e6]])

initialVelocities := Vector(4, {(1) = ` 15 x 3 `*Matrix, (2) = `Data Type: `*anything, (3) = `Storage: `*rectangular, (4) = `Order: `*Fortran_order})

(4)

ic1 := seq(seq(x[i, k](0) = initialPositions[i+1, k], k = 1 .. 3), i = 0 .. N-1); ic2 := seq(seq((D(x[i, k]))(0) = initialVelocities[i+1, k], k = 1 .. 3), i = 0 .. N-1); equations := {ic1, ic2, ode}; sol := dsolve(equations, numeric)

Error, (in dsolve/numeric/process_input) invalid specification of initial conditions, got {x[0, 1](0) = 0, x[0, 2](0) = 0, x[0, 3](0) = 0, x[1, 1](0) = -0.210e8, x[1, 2](0) = 0.426e8, x[1, 3](0) = 0.541e7, x[2, 1](0) = 0.106e9, x[2, 2](0) = -0.244e8, x[2, 3](0) = -0.644e7, x[3, 1](0) = -0.139e9, x[3, 2](0) = -0.569e8, x[3, 3](0) = 0.316e4, x[4, 1](0) = -0.177e9, x[4, 2](0) = -0.155e9, x[4, 3](0) = 0.111e7, x[5, 1](0) = -0.802e9, x[5, 2](0) = 0.131e9, x[5, 3](0) = 0.174e8, x[6, 1](0) = -0.480e9, x[6, 2](0) = -0.142e10, x[6, 3](0) = 0.438e8, x[7, 1](0) = 0.280e10, x[7, 2](0) = 0.103e10, x[7, 3](0) = -0.324e8, x[8, 1](0) = 0.420e10, x[8, 2](0) ...

 

plots[odeplot](sol, [x[1, 1](t), x[1, 2](t), x[1, 3](t)], t = 0 .. 20, numpoints = 1000, axes = normal)

Error, (in plots/odeplot) input is not a valid dsolve/numeric solution

 

plots[odeplot](sol, [seq(x[1, k](t), k = 1 .. 3)], t = 0 .. 20, numpoints = 1000, axes = normal)

Error, (in plots/odeplot) input is not a valid dsolve/numeric solution

 

plots[odeplot](sol, [seq([seq(x[i, k](t), k = 1 .. 3)], i = 0 .. N-1)], t = 0 .. 20, numpoints = 1000, axes = normal)

Error, (in plots/odeplot) input is not a valid dsolve/numeric solution

 

``


Download ass4.mw

Everything works fine until I try to execute the last line. When I do that I get an error that says "Error, in dsolve/numeric/process_input. invalid specifications of initial conditions.

At this point I am not sure if the problem lies in how I have defined my initial conditions or the way i've defined the force equation but I am open to any suggestions or ideas on where I should go from here.

Thanks in advance!

 

Nick

i use the pdsolve to find the solutions of a system of partial differential equations,

but the result contains some indefinite integrals, how to simplify it further?

thank you

code:

eq1 := {6*(diff(_xi[t](x, t, u), u))-3*(diff(_xi[x](x, t, u), u)), 12*(diff(_xi[t](x, t, u), u, u))-6*(diff(_xi[x](x, t, u), u, u)), 2*(diff(_xi[t](x, t, u), u, u, u))-(diff(_xi[x](x, t, u), u, u, u)), diff(_eta[u](x, t, u), t)+diff(_eta[u](x, t, u), x, x, x)+(diff(_eta[u](x, t, u), x))*u, 18*(diff(_xi[t](x, t, u), x, u))+3*(diff(_eta[u](x, t, u), u, u))-9*(diff(_xi[x](x, t, u), x, u)), 6*(diff(_xi[t](x, t, u), x, x))+3*(diff(_eta[u](x, t, u), x, u))-3*(diff(_xi[x](x, t, u), x, x)), 6*(diff(_xi[t](x, t, u), x, u, u))+diff(_eta[u](x, t, u), u, u, u)-3*(diff(_xi[x](x, t, u), x, u, u)), 12*(diff(_xi[t](x, t, u), u))-6*(diff(_xi[x](x, t, u), u))+6*(diff(_xi[t](x, t, u), x, x, u))-6*(diff(_xi[t](x, t, u), u))*u+3*u*(diff(_xi[x](x, t, u), u))-3*(diff(_xi[x](x, t, u), x, x, u))+3*(diff(_eta[u](x, t, u), x, u, u)), 12*(diff(_xi[t](x, t, u), x))-6*(diff(_xi[x](x, t, u), x))+2*(diff(_xi[t](x, t, u), t))+2*(diff(_xi[t](x, t, u), x, x, x))-4*(diff(_xi[t](x, t, u), x))*u+2*(diff(_xi[x](x, t, u), x))*u+_eta[u](x, t, u)-(diff(_xi[x](x, t, u), t))+3*(diff(_eta[u](x, t, u), x, x, u))-(diff(_xi[x](x, t, u), x, x, x))};

simplify(pdsolve(eq1))

 

I read in the net that the method used in pdsolve numeric is the theta method, my question: is it the most efficient with regard to rate of convergence of the numerical solution of the PDE?

If not then why is it used as the default method?

 

Thanks.

 

nullspace or reducedform or Eigenvectors still can not find eigenvector in terms of  mmm , how to find this?

 

mmm is a variable

 in eigenvector using nullspace and eigenvector using maple function  Eigenvectors ? 

I'm reading a string from a textbox, and I need to know where the line breaks are. Hint:They are not found by searching for \n.

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