Maple 16 Questions and Posts

These are Posts and Questions associated with the product, Maple 16

Let be the number z so that |z+3-2*I| + |z-3-8*I| = 6*sqrt(2). Find min and max of the modulus of z. How can I find min and max of modulus of z with Maple.

Thank for your help!

How to manually switch frames in the DifferentialGeometry package? (Example: Help_Differential geometry_lesson2_exercise 4). Thank you

Maple 16 code

 

N1 := FileTools[Text][CountLines](g)

I encounter an error message

in FileTools:-Text:-CountLines) permission denied

What  went wrong ?  This never happened before

I  re install  Maple 16, the same error persists.

 

Please help

Martin
 


Please help me on this :

restart; with(PDETools), with(plots)

n := .3:

Eq1 := (1-n)*(diff(f(x, y), `$`(y, 3)))+(1+x*cot(x))*f(x, y)*(diff(f(x, y), `$`(y, 2)))-(diff(f(x, y), y))/Da+(diff(f(x, y), y))^2+n*We*(diff(f(x, y), `$`(y, 2)))*(diff(f(x, y), `$`(y, 3)))+sin(x)*(theta(x, y)+phi(x, y))/x = x*((diff(f(x, y), y))*(diff(f(x, y), y, x))+(diff(f(x, y), `$`(y, 2)))*(diff(f(x, y), x))):

Eq2 := (diff(theta(x, y), `$`(y, 2)))/Pr+Nt*(diff(theta(x, y), y))^2/Pr+Nb*(diff(phi(x, y), y))*(diff(theta(x, y), y))/Pr+(1+x*cot(x))*f(x, y)*(diff(theta(x, y), y)) = x*((diff(f(x, y), y))*(diff(theta(x, y), x))+(diff(theta(x, y), y))*(diff(f(x, y), x))):

Eq3 := Nb*(diff(phi(x, y), `$`(y, 2)))/(tau*Pr)+Nt*(diff(theta(x, y), `$`(y, 2)))/(tau*Pr)+(1+x*cot(x))*f(x, y)*(diff(phi(x, y), y)) = x*((diff(f(x, y), y))*(diff(phi(x, y), x))+(diff(phi(x, y), y))*(diff(f(x, y), x))):

ValWe := [0, 5, 10]:

bcs := {Nb*(D[2](phi))(x, 0)+Nt*(D[2](theta))(x, 0) = 0, f(0, y) = ((1/12)*y)^2*(6-8*((1/12)*y)+3*((1/12)*y)^2), f(x, 0) = 0, phi(0, y) = -.5*y, phi(x, 12) = 0, theta(0, y) = (1-(1/12)*y)^2, theta(x, 0) = 1, theta(x, 12) = 0, (D[2](f))(x, 0) = Da^(1/2)*(D[2, 2](f))(x, 0)+Da*(D[2, 2, 2](f))(x, 0), (D[2](f))(x, 12) = 0}:

pdsys := {Eq1, Eq2, Eq3}:

p1 := ans[1]:-plot(theta(x, y), x = 1, color = blue):

plots[display]({p1, p2, p3})

 

``


 

Download untitle_2_(1).mw

Download 2222222222222222222.mw

 

> restart; 
> A[0] := 10^(-3); a := 10^5;
> sys := diff(R(theta), theta) = A[0]*exp(2*mu(theta))*sin(theta)/(2*a), R(theta) = 2*exp(-2*mu(theta))*(1-(diff(mu(theta), `$`(theta, 2)))-cot(theta)*(diff(mu(theta), theta)));
> cond := R(0) = 10^(-5), mu(0) = 118.92, (D(mu))(0) = 0;
> F := dsolve({cond, sys}, [R(theta), mu(theta)], numeric);
> with(plots);
> odeplot(F, [theta, R(theta)], 0 .. 3.14, color = black, thickness = 3, linestyle = 4)
> odeplot(F, [theta, mu(theta)], 0 .. 3.14, color = blue, thickness = 3, linestyle = 1)

After last two lines maple writes:

Warning, cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up

And gives me empty plots. I can't figure out where an error can be. Some things I noticed:

Maple doesn't calculate the system before and after zero. If I change the range from 0..3.14 to -10..10 or to 0.00001..0.00001, it gives me 2 errors for 1 plot.

Also if I change the condition mu(0) = 118.92 to mu(0) = 1 or mu(0) = 50 or mu(0) = 80, it works. After ~80 it gives an error. I can't imagine where could appear a division by 0 or some other mistake.

I have been trying to find a solution for the equation below. Is there a non numerical explicit solution?
 

restart

with(DEtools)

[AreSimilar, Closure, DEnormal, DEplot, DEplot3d, DEplot_polygon, DFactor, DFactorLCLM, DFactorsols, Dchangevar, Desingularize, FunctionDecomposition, GCRD, Gosper, Heunsols, Homomorphisms, IVPsol, IsHyperexponential, LCLM, MeijerGsols, MultiplicativeDecomposition, ODEInvariants, PDEchangecoords, PolynomialNormalForm, RationalCanonicalForm, ReduceHyperexp, RiemannPsols, Xchange, Xcommutator, Xgauge, Zeilberger, abelsol, adjoint, autonomous, bernoullisol, buildsol, buildsym, canoni, caseplot, casesplit, checkrank, chinisol, clairautsol, constcoeffsols, convertAlg, convertsys, dalembertsol, dcoeffs, de2diffop, dfieldplot, diff_table, diffop2de, dperiodic_sols, dpolyform, dsubs, eigenring, endomorphism_charpoly, equinv, eta_k, eulersols, exactsol, expsols, exterior_power, firint, firtest, formal_sol, gen_exp, generate_ic, genhomosol, gensys, hamilton_eqs, hypergeomsols, hyperode, indicialeq, infgen, initialdata, integrate_sols, intfactor, invariants, kovacicsols, leftdivision, liesol, line_int, linearsol, matrixDE, matrix_riccati, maxdimsystems, moser_reduce, muchange, mult, mutest, newton_polygon, normalG2, ode_int_y, ode_y1, odeadvisor, odepde, parametricsol, particularsol, phaseportrait, poincare, polysols, power_equivalent, rational_equivalent, ratsols, redode, reduceOrder, reduce_order, regular_parts, regularsp, remove_RootOf, riccati_system, riccatisol, rifread, rifsimp, rightdivision, rtaylor, separablesol, singularities, solve_group, super_reduce, symgen, symmetric_power, symmetric_product, symtest, transinv, translate, untranslate, varparam, zoom]

(1)

``

sol := (JacobiCN((1/10)*sqrt(5)*sqrt(2)*t, (1/3)*sqrt(3))*sqrt(5)+2*sqrt(2))/(JacobiCN((1/10)*sqrt(5)*sqrt(2)*t, (1/3)*sqrt(3))*sqrt(5)+5*sqrt(2))

(JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2))*5^(1/2)+2*2^(1/2))/(JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2))*5^(1/2)+5*2^(1/2))

(2)

sol1 := diff(psi(t), t) = sol

diff(psi(t), t) = (JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2))*5^(1/2)+2*2^(1/2))/(JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2))*5^(1/2)+5*2^(1/2))

(3)

odeadvisor(sol1, psi(t))

[_quadrature]

(4)

sol2 := dsolve({sol1, psi(0) = 0})

psi(t) = Int((JacobiCN((1/10)*_z1*10^(1/2), (1/3)*3^(1/2))*5^(1/2)+2*2^(1/2))/(JacobiCN((1/10)*_z1*10^(1/2), (1/3)*3^(1/2))*5^(1/2)+5*2^(1/2)), _z1 = 0 .. t)

(5)

``

``

sol3 := convert(sol, parfrac)

1-(3/5)*2^(1/2)*5^(1/2)/(JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2))+2^(1/2)*5^(1/2))

(6)

sol4 := diff(psi(t), t) = sol3

diff(psi(t), t) = 1-(3/5)*2^(1/2)*5^(1/2)/(JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2))+2^(1/2)*5^(1/2))

(7)

dsolve({sol4, psi(0) = 0})

psi(t) = Int(-(3/5)*10^(1/2)/(JacobiCN((1/10)*_z1*10^(1/2), (1/3)*3^(1/2))+10^(1/2)), _z1 = 0 .. t)+t

(8)

sol5 := diff(psi(t), t) = 3*sqrt(2)*sqrt(5)/(5*(JacobiCN((1/10)*sqrt(5)*sqrt(2)*t, (1/3)*sqrt(3))+sqrt(5)*sqrt(2)))

diff(psi(t), t) = 3*2^(1/2)*5^(1/2)/(5*2^(1/2)*5^(1/2)+5*JacobiCN((1/10)*5^(1/2)*2^(1/2)*t, (1/3)*3^(1/2)))

(9)

odeadvisor(sol5)

[_quadrature]

(10)

dsolve({sol5})

{psi(t) = Int((3/5)*10^(1/2)/(JacobiCN((1/10)*t*10^(1/2), (1/3)*3^(1/2))+10^(1/2)), t)+_C1}

(11)

``


 

Download Jacobi_Diff_eqn_Mapleprime_post.mw

When I try the example from Maple Help for LPSolve (I use Windows)

with(Optimization);
LPSolve(-4*x-5*y, {0 <= x, 0 <= y, x+2*y <= 6, 5*x+4*y <= 20});

I do not get the same solution like in the example: [-19., [x = 2.66666666666667, y = 1.66666666666667]]
Instead I get

Warning, problem appears to be unbounded
            [0., [x = HFloat(0.0), y = HFloat(0.0)]]


My Professor uses the same version, but with Linux and do not have such problems. Why my installation does not solve the standart Help example?

Thank you

f1:=(1/s^2)^N;

Maple failed to convert it into  f1:=s^(-2N);

 

Hi! 

Tried to solve the PDE below (q and p are time-dependent variabels, q(t),p(t)):

pde := diff(rho(t, q, p), t) = -(diff(rho(t, q, p), q))*p+(diff(rho(t, q, p), p))*(2*q+2);
          

pdsolve(pde, rho(t, q, p));
           

And got the answer: 

rho(t, q, p) = _F1(p^2+2*q^2+4*q, -(1/2)*sqrt(2)*arctan((q+1)*sqrt(2)*(1/sqrt(p^2)))+t)

But I'm not sure how to interpret the result. I understand that  _F1 is an arbitrary function, but then I get confused with the comma? I thought that I'd get a function of q and p, where they depend on t. 

Best regards
Sannis

 

Hello! 

For the last couple of days I've been trying really hard to solve the linear PDE 

dR/dt = -dRdH/dqdp + dRdH/(dpdq) . Where R is a function R(t,q(t),p(t)) and H is the hamiltonian H=  p^2/2 +q^2 +2*q .

(dH/dp= p and dH/dq= -2q-2), q and p depends on the time t, and I'm supposed to solve the PDE and then plot the gaussian distribution (2D). 

I tried doing this:

pde := diff(R(t, q1(t), p1(t)), t) = -(diff(R(t, q(t), p(t)), q(t)))*p(t)+(diff(R(t, q(t), p(t)), p(t)))*(-2*q(t)-2)

But pdsolve(pde) gives me:  "Error, (in pdsolve/info) the name of the indeterminate function must be given". 

When I change q(t) to q and p(t) to p I get:

R(t, q, p) = _F1(p^2-2*q^2-4*q, -(1/2)*ln(sqrt(2)*q+p+sqrt(2))*sqrt(2)+t)

And then I'm lost. How do I solve this PDE in maple? 

Thankful for any help 

 

 

how to find roots of equation J0(xR) = 0 ,R is constant, using maple? I know command for zeros of Bessel function i.e J0(x) = 0.  but what to do with different argument?

Thank you very much !

I have 

dZ(x)=−xdlog(z(x))

where d is the exterior derivative. I would like to recover the function Z(x) by integrating both sides of the equation. How would I compute this in Maple?

I'm trying to compute the tensor product of two column vectors as

 

with(LinearAlgebra):

A:=Matrix([[1/sqrt(2)],[0],[0],[1/sqrt(2)]]);

KroneckerProduct(A,A);

 

And the output is a column vector with entries: "16 x 1 Matrix", "Data Type: Anything", "Storage: rectangular", "Order: Fortran_order"

 

The Maple documentation indicates that this function should output the result of the kronecker tensor product of the input matrices, and I've followed the same form as the examples in the documentation... Does anyone know why this isn't working as it should?

The page ?type,piecewise shows the example

type(piecewise[](x < 1, a, b), 'piecewise');

and lines 4-8 of showstat(`print/piecewise`) deal with the case of an indexed piecewise. Yet I can find no other reference to indexed piecewise. What is it used for? When I put an index on a piecewise, nothing special seems to happen, either computationally or display-wise:

piecewise[abs](x > 0, x, -x);
piecewise[Carl](x > 0, x, -x);

The code in `print/piecewise` suggests that it serves some purpose.

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