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Hello

I have a subscripts error, or it seems to be an error.

As you can see on the picture, then I have defined the varible I__K, but when I need it again I get another result or It seems to be another result that looks like this I[K]. I use the esc buttom to recall the varible.

Are there anybody that has a solution to this? I have been looking at other treads, but there seems not to be a solution that works or maybe I'm looking the wrong places.

Regards

Heide

 

 

How difficult is it to simulate gravitational influences and perturbing effects on celestial orbits with Maple? Could this syntax http://www.maplesoft.com/applications/view.aspx?SID=4484&view=html be altered without excessive changes to consider these aspects?

Are there somewhere worksheets to take a look at as an introduction and to see how such goals would be approached and implemented?


with(PDEtools, casesplit, declare)
``

L := 1651.12; m := 3205.12; r1 := .1875; r2 := 2; z1 := 0; z2 := 12; ld := 4.5

NULL

declare(u(r, z), w(r, z))``

with(DEtools, gensys)

rr := (L+2*m)*(diff(u(r, z), r))+L*(diff(w(r, z), z))+L*u(r, z)/r

zz := L*(diff(u(r, z), r))+(L+2*m)*(diff(w(r, z), z))+L*u(r, z)/r

rz := m*(diff(u(r, z), z))+m*(diff(w(r, z), r))

BCS := {rr(r1, ld) = 0, rz(r1, z) = T, w(r, 0) = 0, zz(r, z2) = 0}

{3205.12*(diff(u(r, z), z))(.1875, z)+3205.12*(diff(w(r, z), r))(.1875, z) = T, 8061.36*(diff(u(r, z), r))(.1875, 4.5)+1651.12*(diff(w(r, z), z))(.1875, 4.5)+1651.12*(u(r, z))(.1875, 4.5)/r(.1875, 4.5) = 0, 1651.12*(diff(u(r, z), r))(r, 12)+8061.36*(diff(w(r, z), z))(r, 12)+1651.12*(u(r, z))(r, 12)/r(r, 12) = 0, w(r, 0) = 0}

(1)

``

NULL

sys3 := [(L+2*m)*(diff(u(r, z), r, r))+(L+m)*(diff(w(r, z), r, z))+(L+2*m)*(diff(u(r, z), r))/r-(L+2*m)*u(r, z)/r^2+m*(diff(u(r, z), z, z)) = 0, (L+m)*(diff(u(r, z), r, z))+m*(diff(w(r, z), r, r))+(L+2*m)*(diff(w(r, z), z, z))+(L+m)*(diff(u(r, z), z))/r+m*(diff(w(r, z), r))/r = 0]

pdsolve(sys3, BCS, numeric)

 

 

``

``


Download PDE_equation2.mw

Hi all,

I have the following PDE, is it solveable by Maple or not. Do I need a boundary condition and how many or I can get a general solution? I am new to Maple. Any help will be appreciated.

Thank you.

 

 

 

Hi all, 

 

I was wondering if it is possible to add a colour gradient to a point plot to represent another perameter in the data.

 

 

For example, each point corresponds to a value of 'f' ranging from 0.1 to 1, and I was wondering how to display this by means of a colour gradient.

 

 

Thanks,

See attached file and code

0. This is the differential equation I'm trying to do:

http://www.intmath.com/differential-equations/6-rc-circuits.php

https://i.imgur.com/zlVIisR.png

 

1. After you look at the above imgur link, could you help me with this error 

Error, (in Units:-Standard:-+) the units ``Ω`` and `1/F` have incompatible dimensions

  

2. Why does my solve ODE fail? 

 

See my code: 

test_maple.mw

Hello,

 

I'm trying to solve the integral u/(1-u) with Maple and noticed that it returned a result that doesn't accord to the solution I found by hand or the solution from WolframAlpha. This is a screenshot of the weird behaviour:

Does Maple do any weird conversions? Or did I do something wrong or is Maple wrong?

Thanks in advance,

Hi!

In Mathematica 10.0 were introduced regions with functions like TransformedRegion, ReginIntersection, etc. Moreover, it is easy to check if a point is inside a region, etc.

I would like to ask if in Maple I could use some API with similar functionality?. For instance, I would like to get integer points which lay inside an intersection of two cubes. How I could do this in Maple?

 

 

Hi

I've this equation ,what is displacement,

U := sum(C[i]*lambda[i]*h^2*M*(C[13]+C[55])*exp(Z*lambda[i]*M)*cos(M*x)/C[11], i = 1 .. 4);
 But when I used the data ,I do not get the right result

the datas are

h := .25;
M := Pi/L; L := 1;
E[3] := 1; E[1] := 40; E[2] := 1;
1
V[13] := .25; V[31] := .25; V[12] := .25; V[23] := .25; V[32] := .25; V[21] := .25;


G[44] := .2; G[55] := .2; G[66] := .2;

G[13] := .5;

C[55] := G[13];

Omega := -2*V[13]*V[21]*V[32]-V[12]*V[21]-V[13]*V[31]-V[23]*V[32]+1;

C[11] := (-V[23]*V[32]+1)*E[1]/Omega;

C[12] := (V[13]*V[32]+V[12])*E[2]/Omega;


C[33] := (1-V[12]*V[12])*E[3]/Omega;

 

C[1] := -.2596702449; C[2] := -2.411545729; C[3] := -0.6051254981e-1; C[4] := .4085627399;

lambda[1] := .6891428810; lambda[2] := -.6891428810; lambda[3] := 9.177422410; lambda[4] := -9.177422410;

could you help me plase

I read research paper about elasticity, and I don't not how can get the results for displacment ant shaer stress,, could you help me please.

please help me

Kind Regards

 

 

Hello,

My code records the values I need, however, I need to implement a modulo of 2*Pi on my result for theta. But this leads to a graph with no plots and I'm not sure how to fix it. Any help is greatly aprreciated! Thank you in advance!

Kind regards,

Gam

with(plots):

a := 1.501*10^9:

Th := sqrt(4*Pi^2*a^3/(G*(Mh+Msat))):

HyperionOrbit := proc (`θIC`, `ωIC`, n) local a, Mh, Msat, G, e, beta, M, Eqns, ICs, soln; option remember; global `ωH`, Th; a := 1.501*10^9; Mh := 5.5855*10^18; Msat := 5.6832*10^26; G := 6.67259/10^11; e := .232; beta := .89; M := Mh+Msat; Eqns := diff(theta(t), t) = omega(t), diff(omega(t), t) = -G*Msat*beta^2*(xH(t)*sin(theta(t))-yH(t)*cos(theta(t)))*(xH(t)*cos(theta(t))+yH(t)*sin(theta(t)))/(xH(t)^2+yH(t)^2)^2.5, diff(xH(t), t) = vxH(t), diff(vxH(t), t) = -G*M*xH(t)/(xH(t)^2+yH(t)^2)^(3/2), diff(yH(t), t) = vyH(t), diff(vyH(t), t) = -G*M*yH(t)/(xH(t)^2+yH(t)^2)^(3/2); ICs := xH(0) = a*(1+e), yH(0) = 0, vxH(0) = 0, vyH(0) = sqrt(G*M*(1-e)/(a*(1+e))), theta(0) = `θIC`, omega(0) = `ωIC`; soln := dsolve({Eqns, ICs}, numeric, maxfun = 0, output = array([seq(i, i = 0 .. n*Th, Th)])); plots:-odeplot(soln, [modp(theta(t), 2*Pi), omega(t)/`ωH`], 0 .. n*Th, labels = ["θ(t)","ω(t)/ωH"], axes = boxed, style = plottools:-point, size = [.25, .75]) end proc:

plots:-display(HyperionOrbit(.5, 1.8*`ωH`, 10));

Download Poincare_section_Boyd_plot_fixing_theta.mw

bia Man

Hello,

I've been trying to collect points at certain intervals in my plot, however, the sample option doesn't seem to be working. Can anyone lend me a hand? Any help is greatly appreciated! Thank you in advance!

Kind regards,

Gam

with(plots):

a := 1.501*10^9:

Th := sqrt(4*Pi^2*a^3/(G*(Mh+Msat))):

HyperionOrbit := proc (`θIC`, `ωIC`, n) local a, Mh, Msat, G, e, beta, M, Eqns, ICs, soln; global `ωH`, Th; a := 1.501*10^9; Mh := 5.5855*10^18; Msat := 5.6832*10^26; G := 6.67259/10^11; e := .232; beta := .89; M := Mh+Msat; Eqns := diff(theta(t), t) = omega(t), diff(omega(t), t) = -G*Msat*beta^2*(xH(t)*sin(theta(t))-yH(t)*cos(theta(t)))*(xH(t)*cos(theta(t))+yH(t)*sin(theta(t)))/(xH(t)^2+yH(t)^2)^2.5, diff(xH(t), t) = vxH(t), diff(vxH(t), t) = -G*M*xH(t)/(xH(t)^2+yH(t)^2)^(3/2), diff(yH(t), t) = vyH(t), diff(vyH(t), t) = -G*M*yH(t)/(xH(t)^2+yH(t)^2)^(3/2); ICs := xH(0) = a*(1+e), yH(0) = 0, vxH(0) = 0, vyH(0) = sqrt(G*M*(1-e)/(a*(1+e))), theta(0) = `θIC`, omega(0) = `ωIC`; soln := dsolve({Eqns, ICs}, numeric, maxfun = 0); plots:-odeplot(soln, [theta(t), omega(t)/`ωH`], 0 .. n*Th, numpoints = 2000, labels = ["θ(t)","ω(t)/ωH"], axes = boxed, style = point, sample = [seq(i, i = 0 .. n*Th, Th)]) end proc:

HyperionOrbit(.5, 1.8*`ωH`, 10)

Error, (in plot/options2d) unexpected option: sample = [0, 1876321.326, 3752642.652, 5628963.978, 7505285.304, 9381606.630, 11257927.96, 13134249.28, 15010570.61, 16886891.93, 18763213.26]

 

``

``

 

Download Poincare_section.mw

bia Man

Hello,

I've got this error in my code and I don't know why as I didn't get it when I used a different xn function. Any help would be greatly appreciated! Thank you in advance!

Kind regards,

Gambia Man

restart

with(plots):

boxcount := proc (data, N) local n, xmax, xmin, xrange, ymax, ymin, yrange, dx, dy, i, j, ix, iy, sum, res; n := (1/2)*ArrayNumElems(data); xmax := max(seq(data[i, 1], i = 1 .. n)); xmin := min(seq(data[i, 1], i = 1 .. n)); ymax := max(seq(data[i, 2], i = 1 .. n)); ymin := min(seq(data[i, 2], i = 1 .. n)); xrange := xmax-xmin; xmin := xmin+(-1)*0.1e-1*xrange; xmax := xmax+0.1e-1*xrange; xrange := 1.02*xrange; yrange := ymax-ymin; ymin := ymin+(-1)*0.1e-1*yrange; ymax := ymax+0.1e-1*yrange; yrange := 1.02*yrange; dx := xrange/N; dy := yrange/N; res := Array(0 .. N-1, 0 .. N-1, 0); for i to n do ix := trunc((data[i, 1]-xmin)/dx); iy := trunc((data[i, 2]-ymin)/dy); res[ix, iy] := 1 end do; add(add(res[i, j], i = 0 .. N-1), j = 0 .. N-1) end proc:

``

bicationplot := proc (N) local Nr, Nt, x0, rmin, rmax, bif, k, ir, r, xn, i; global pts; Nr := 100; Nt := 200; x0 := .1; rmin := .75; rmax := 3.5; bif := Array(1 .. Nr*N, 1 .. 2); k := 1; for ir to Nr do r := rmin+ir*(rmax-rmin)/Nr; xn := x0; for i to Nt do xn := xn^2-r end do; for i to N do xn := xn^2-r; bif[k, 1] := r; bif[k, 2] := xn; k := k+1 end do end do; pts := bif end proc:

bif

bif

(1)

fractaldimension := proc (Noofitterations::integer, Npoints::integer, Nmax::integer) local res, xv, yv, line, stderrors, avgstderrors, i, avgline; avgstderrors := 0; avgline := 0; for i to Noofitterations do bicationplot(Npoints); res := [seq([1.0/n, boxcount(pts, n)], n = 1 .. Nmax, 10)]; xv := [seq(log(res[i][1]), i = 1 .. nops(res))]; yv := [seq(log(res[i][2]), i = 1 .. nops(res))]; line[i] := Fit(m*x+const, xv, yv, x, output = [leastsquaresfunction]); stderrors[i] := Fit(m*x+const, xv, yv, x, output = standarderrors) end do; for i to Noofitterations do avgstderrors := avgstderrors+stderrors[i] end do; avgstderrors := avgstderrors/Noofitterations; for i to Noofitterations do avgline := avgline+line[i] end do; avgline := avgline/Noofitterations; return FD = -(diff(avgline, x)), avgline, avgstderrors, loglogplot(res) end proc:

fractaldimension(10, 100, 100)

Error, (in boxcount) bad index into Array

 

``

 

Download First_part_fractal_determination_.mw

Hello,

I would like to know how to order a sequence of number from smallest to largest. This is if I have both real and imaginary numbers. Any help would be rgeatly appreciated! Thank you in advance.

Kind regards,

Gamiba Man

hello

I have recently install Maple17 on my computer (Windows10) and I need to use some Greece alphabet such as ß but I look everywhere in maple's icon and I just could find capital Greece alphabet.

does anybody know how can I find those?

Hello,

In this procedure I get the error, 

Error, `:=` unexpected

I know what it means I just can't seem to resolve it. Any help would be greatly appreciated! Thank you in advance for looking at this code!

Kind regards,

Gambia Man

HamilMat := proc (K::integer) local ni, mi, nj, mj, N, Hamil, Eigenvec, i, j, res; option remember; global Vij, U, L; N := K^2; ni := Vector(N); mi := Vector(N); nj := Vector[row](N); mj := Vector[row](N); for i to N do for j to K do res := (i+K-j)/K; if type(res, integer) = true then ni[i] := j; nj[i] := j; mi[i] := res; mj[i] := res end if end do end do; Hamil := Matrix(N, shape = symmetric); for i to N do for j from i to N do if i <> j then Hamil(i, j) := Vij(ni[i], mi[i], nj[j], mj[j]) elif i = j then Hamil(i, j) := Vij(ni[i], mi[i], nj[j], mj[j])+(1/2)*(ni[i]^2+mi[i]^2)*Pi^2/L^2 end if end do end do; return Eigenvec := Eigenvectors(Hamil, output = ['values', 'vectors']), Hamil end proc

Error, `:=` unexpected

 

 

Download small_error.mw

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