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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

As an Arts major at the University of Waterloo, my first day as a co-op student in the Maplesoft marketing department was a bit of a blur. I was hearing a lot of mathematical jargon that I did not understand. Other than a mandatory statistics class in my second year at university, I haven’t taken a math course since high school, over two years ago. I spent my first week as the marketing assistant educating myself about the basics of marketing complex math software. My favourite method for doing this was to read through the Maplesoft user stories. As I read, I was amazed by the variety of customers and the endless applications that Maplesoft products had contributed to. It became apparent that math is a part of every industry and it is in the design of many products. There were a few stories from the robotics industry in particular that really sparked my interest in the software that I now market. 

 

We’ve all seen the futuristic movies where robots gradually get smarter and smarter, developing enough intelligence to control the human race, and eventually, take over the world. As it turns out, Engineered Arts, a UK robotics company, is bringing us one step closer to that reality. Well… they’re maybe not ready for world domination just yet, but they are working on one of the most advanced and human-like robots that the world has seen outside of a Hollywood production, and they are doing this using MapleSim. The first generation of the biologically inspired robot was named RoboThespian. With his ability to speak and sing, he was used to educate, entertain, and investigate new developments in robotics. However, he was largely static. That’s when the engineers began work on generation two of their robot, named Byrun, who has the ability to walk, run, jump, and hop as well as speak and sing. Byrun can even express thousands of different facial features thanks to his projective head display. This makes him even more human-like; scary or cool? I’m thinking a bit of both. If you’re interested in the story, click here to continue reading about it.

 

Another unexpected use of MapleSim was adopted as a joint research project between Ryerson University and McMaster University. I never would have guessed that math software could be applied to the process of human birth. Nevertheless, a group of researchers used MapleSim to simulate induced labour with a Foley Catheter. In short, this is when a small balloon is inserted through the opening of the cervix creating a downward pressure that effectively tricks the cervix into opening for labour to begin. Though the application of this story surprised me, it makes a lot of sense to use modelling software for a research project like this. It’s more efficient to get all of the kinks out of the virtual model in a simulation program before building a physical model that could end up being dysfunctional. According to Dr. James Andrew Smith, a Biomedical Engineering researcher and Assistant Professor in Electrical and Computer Engineering, who is the lead researcher on the project, “Modern engineering has a lot to offer the medical world,” especially when it saves on time and cost. Click here to read more about this story and to watch a video of the finished model.

 

After two months at Maplesoft, I have noticed that I don’t look at things in the same way that I used to. I find myself staring at a toaster and imagining how it was designed. Did the engineers use advanced physical simulation and modeling software to make the most efficient toaster possible? Well, if it can still only toast on one side then, my guess is no! Maplesoft has many more user stories that I haven’t had the chance to read yet. With customers ranging from BMW to Pixar, Maplesoft continues to expand its customer base and adapt its software to support more and more unique applications. I can’t wait to hear what new and unexpected things will be done with the software next!

 

Hello,

I'm writing a code and I seem to have an issue when trying to implement a procedure. Here is the code:

 

with(plots):

Z := 75; A := 189; k := 14.6; Rm := 8*R; r0 := 10^(-8)*R; c := 137.036; ms := 105.66/(.51100)

fmtoau := 10^(-15)/(0.529177e-1*10^(-9)):

R := 1.1*fmtoau*A^(1.0/(3.0)):

f := proc (x) options operator, arrow; 1/(1+exp(k*(x-1))) end proc:

n0 := 3*Z*k^2/(4*Pi*(Pi^2+k^2)*R^3):

n := proc (r) options operator, arrow; 4*Pi*n0*f(r/R) end proc:

int(r^2*n(r), r = 0 .. Rm);

73.00000007

(1)

plot(n/n0, 0 .. 2*R);

 

v1 := unapply(int(x^2*f(x), x), x):

Vfermi := proc (r) options operator, arrow; -4*Pi*n0*R^2*(R*(v1(r/R)-v10)/r+v2Rm-v2(r/R)) end proc:

Vuniform := proc (r) options operator, arrow; piecewise(r < R, -Z*(3/2-(1/2)*r^2/R^2)/R, -Z/r) end proc:

plot([Vuniform(r), Vfermi(r), -Z/r], r = r0 .. 2*R, V = 1.2*Vfermi(r0) .. 0, legend = ["uniform charge", "Fermi distribution", "point charge"]);

 

``

plotsol1s := proc (E, K, r0, S, col) local Eqns, ICs, fnl, gnl, r, soln; global ms, c; Eqns := diff(fnl(r), r) = gnl(r)*[E+2*ms*c^2-Vuniform(r)]/c-(K+1)*fnl(r)/r, diff(gnl(r), r) = -fnl(r)*[E-Vuniform(r)]/c-(1-K)*fnl(r)/r; ICs := fnl(r0) = 1, gnl(r0) = 0; soln := dsolve({Eqns, ICs}, numeric); plots:-odeplot(soln, [r, fnl(r)], r0 .. S, color = col) end proc:

plotsol1s(-3*10^5, -1, 10^(-10), Rm, red)

Error, (in f) unable to store '[HFloat(0.0)]' when datatype=float[8]

 

``

``


Any help would be greatly appreciated.

 

Gambia Man

 

Hi everyone,

 

I'm trying to solve the following eqauation but Maple gives me the answer (( RootOf(mexp(-_Z*(m-1))*d^2-theta+_Z*theta-theta*c*t__kj) ))

 

The equation is:

solve(mexp(-(m-1)*t__ij)*d^2-theta+theta*t__ij-theta*(sum(t__kj, k = 1 .. c))-m*eta*(diff((1-1/exp(t))^m, t)) = 0, t__ij);

 

Could you please help me??

 

What is the meaning rootOF? Is there any explicit solution to that equation??

 

Thank you for your help

Hi everyone,

I'm trying to solve the following equation and unfortunately I get this error ( Error, (in Engine:-Dispatch) invalid subscript selector ) each time I try. Could you please help me??

I will be thankful for your great help.

solve(m*exp(-(m-1)*tij)*d2-θ+θ*tij-θ*(Σ(tkj, k = 1 .. c))-m*η*(1-exp(-tij))(m-1) = 0, tij)

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