Questions - MaplePrimes

How can change the shape of plot in contour by usi...

Asked by: SSMB 100

February 24 2025

1 7

i want try all number to my parameter for check the shape of plot there is any way for doing that?

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M := 4*b^2*beta*((a*y-2*alpha*t+x)*b^2+a*(-2*beta*t+a*(a*y-2*alpha*t+x)))/(-b^6*beta*y^2+(-4*t*y*beta^2+(-2*a^2*y^2+(4*(alpha*t-(1/2)*x))*y*a-4*(alpha*t-(1/2)*x)^2)*beta+3*a)*b^4+(-4*t^2*beta^3+4*a*t*(a*y-2*alpha*t+x)*beta^2-a^2*(a*y-2*alpha*t+x)^2*beta+6*a^3)*b^2+3*a^5)

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(1)

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Download control-trajectory.mw

quick design question regarding my animation...

Asked by: jalal 435

February 24 2025

0 1

Hi,

just a quick design question regarding my animation. The color "AliceBlue" disappears from my background... Could it be a background option issue?

Q_AlceBlue_background.mw

bug report: Maple dsolve throws internal error on ...

Asked by: nm 11353

February 24 2025

3 4

THis IC for Abel ode is not valid and should result in no solution. But instead of returning NULL, dsolve throws internal error called Error, (in dsolve) invalid limiting point

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restart;

>	interface(version);

>	Physics:-Version();

>	ode:=diff(y(x),x)-x^ay(x)^3+3y(x)^2-x^(-a)y(x)-x^(-2a)+a*x^(-a-1) = 0;

>	DEtools:-odeadvisor(ode); sol:=dsolve([ode,y(1)=1])

Error, (in dsolve) invalid limiting point

>	tracelast;

dsolve called with arguments: [diff(y(x), x)-x^a*y(x)^3+3*y(x)^2-x^(-a)*y(x)-x^(-2*a)+a*x^(-a-1) = 0, y(1) = 1], arbitraryconstants = subscripted, atomizenames = true, build = false, numeric = false, type = none
#(dsolve,80): error

\`dsolve/IC\` called with arguments: [diff(y(x), x)-x^a*y(x)^3+3*y(x)^2-x^(-a)*y(x)-x^(-2*a)+a*x^(-a-1) = 0, y(1) = 1], {y(x)}, skipimplicit = false, skippparticularsolforlinearODEs = true, solution = {}, usesolutions = particular and general
#(\`dsolve/IC\`,64): draft := procname(_passed,':-usesolutions = "general"');

\`dsolve/IC\` called with arguments: [diff(y(x), x)-x^a*y(x)^3+3*y(x)^2-x^(-a)*y(x)-x^(-2*a)+a*x^(-a-1) = 0, y(1) = 1], {y(x)}, skipimplicit = false, skippparticularsolforlinearODEs = true, solution = {}, usesolutions = general
#(\`dsolve/IC\`,277): zz := map(op,{\`dsolve/IC/_C\`({ANS[i]},funcs,x,ics)});

\`dsolve/IC/_C\` called with arguments: {y(x) = -exp(2*x^(-a+1)/(a-1))/(_C[1]-2*2^(2*(a+1)/(a-1))*(1/(-a+1))^((a+1)/(a-1))*(2^(-(5*a-3)/(a-1))*(1/(-a+1))^(-(a+1)/(a-1))*x^(2*a)*(-a+1)^2*(x^(-a+1)/(-a+1))^(1/(a-1))*(-4*x^(-a+1)*a^2/(-a+1)+8*a*x^(-a+1)/(-a+1)-4*x^(-a+1)/(-a+1)+2*a-2)*WhittakerM(-(a+1)/(a-1)+1/(a-1), -1/(a-1)+1/2, 4*x^(-a+1)/(-a+1))*exp(-2*x^(-a+1)/(-a+1))/((a+1)*(-3+a))-2^(-(3*a-1)/(a-1))*(1/(-a+1))^(-(a+1)/(a-1))*x^(2*a)*WhittakerM(-(a+1)/(a-1)+1/(a-1)+1, -1/(a-1)+1/2, 4*x^(-a+1)/(-a+1))*(-a+1)^2*(x^(-a+1)/(-a+1))^(1/(a-1))*exp(-2*x^(-a+1)/(-a+1))/((a+1)*(-3+a)))/(-a+1))^(1/2)+x^(-a)}, {y(x)}, x, [y(1) = 1]
#(\`dsolve/IC/_C\`,1): ans := \`dsolve/IC/_C/do\`(solns,depvars,t,inits,'evaluated_ans', "default",':-giveup = giveup');

\`dsolve/IC/_C/do\` called with arguments: {y(x) = -exp(2*x^(-a+1)/(a-1))/(_C[1]-2*2^(2*(a+1)/(a-1))*(1/(-a+1))^((a+1)/(a-1))*(2^(-(5*a-3)/(a-1))*(1/(-a+1))^(-(a+1)/(a-1))*x^(2*a)*(-a+1)^2*(x^(-a+1)/(-a+1))^(1/(a-1))*(-4*x^(-a+1)*a^2/(-a+1)+8*a*x^(-a+1)/(-a+1)-4*x^(-a+1)/(-a+1)+2*a-2)*WhittakerM(-(a+1)/(a-1)+1/(a-1), -1/(a-1)+1/2, 4*x^(-a+1)/(-a+1))*exp(-2*x^(-a+1)/(-a+1))/((a+1)*(-3+a))-2^(-(3*a-1)/(a-1))*(1/(-a+1))^(-(a+1)/(a-1))*x^(2*a)*WhittakerM(-(a+1)/(a-1)+1/(a-1)+1, -1/(a-1)+1/2, 4*x^(-a+1)/(-a+1))*(-a+1)^2*(x^(-a+1)/(-a+1))^(1/(a-1))*exp(-2*x^(-a+1)/(-a+1))/((a+1)*(-3+a)))/(-a+1))^(1/2)+x^(-a)}, {y(x)}, x, [y(1) = 1], evaluated_ans, default, giveup = giveup, usecansolve = false
#(\`dsolve/IC/_C/do\`,133): Solns := map((u, S) -> map(limit,S,op(u)),csol,Solns);

limit called with arguments: y(x) = -exp(2*x^(-a+1)/(a-1))/(_C[1]-2*2^(2*(a+1)/(a-1))*(1/(-a+1))^((a+1)/(a-1))*(2^(-(5*a-3)/(a-1))*(1/(-a+1))^(-(a+1)/(a-1))*x^(2*a)*(-a+1)^2*(x^(-a+1)/(-a+1))^(1/(a-1))*(-4*x^(-a+1)*a^2/(-a+1)+8*a*x^(-a+1)/(-a+1)-4*x^(-a+1)/(-a+1)+2*a-2)*WhittakerM(-(a+1)/(a-1)+1/(a-1), -1/(a-1)+1/2, 4*x^(-a+1)/(-a+1))*exp(-2*x^(-a+1)/(-a+1))/((a+1)*(-3+a))-2^(-(3*a-1)/(a-1))*(1/(-a+1))^(-(a+1)/(a-1))*x^(2*a)*WhittakerM(-(a+1)/(a-1)+1/(a-1)+1, -1/(a-1)+1/2, 4*x^(-a+1)/(-a+1))*(-a+1)^2*(x^(-a+1)/(-a+1))^(1/(a-1))*exp(-2*x^(-a+1)/(-a+1))/((a+1)*(-3+a)))/(-a+1))^(1/2)+x^(-a), _C[1] = exp((4*I)*Im(1/(a-1)))*infinity, parametric = false
#(limit,2): return map(thisproc,_passed)

limit called with arguments: y(x), _C[1] = exp((4*I)*Im(1/(a-1)))*infinity, parametric = false
#(limit,33): error "invalid limiting point"

Error, (in dsolve) invalid limiting point

locals defined as: ddir = ddir, dexpr = y(x), fexpr = fexpr, r = r, x = _C[1], fL = fL, L = exp((4*I)*Im(1/(a-1)))*infinity, efloat = efloat, lfloat = lfloat, ind_dexpr = ind_dexpr, ind_L = ind_L, lexpr = lexpr, t = t, limr = limr, liml = liml, pt = (_C[1] = exp((4*I)*Im(1/(a-1)))*infinity), inertfunctions = {}, limitX = limitX, parameters = parameters, Y = Y, limc = limc, cexpr = cexpr, texpr = texpr, bexpr = bexpr, limt = limt, limb = limb, param = param, c = c, N = N, Z = Z, P = P, o = o, e = e, uneval = uneval, i = i, A = A, cond = cond, ll = ll, rr = rr

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Download internal_error_instead_of_no_solution.mw

Equivalent of currentdir, but not to get current w...

Asked by: AmirHosein Sadeghimanesh 225

February 23 2025

0 4

Is there an equivalent of currentdir() which instead of returning current working directory, returns the directory of the file being read. So assume I have an ".mm" or ".mpl" file saved in some location and there is another file with a location fixed relative to this file, but not fixed in absolute location on the computer and not fixed relative with current working directory. One natural thing is to have a line in the first file that takes its current location (not current working location of the user!) and then use the fixed relative path info, and then gives the location of the second file to the user. Using currendir won't help here because current working directory is not necessarily the same as the location of the file you are reading, the first file. One may say the user is reading the first file so he knows already its location, right? Well, if the user is also the writer of the file, sure, not a problem, he can manually edit the lines of the file and put that location inside the file instead of using currentdir etc. However, if the user is not the writer and also does not know how to edit or whatever else reason, then the file should be able to inform Maple of its own location, so that's why something like currentdir() but not for the working directory, instead for currently being read file's directory is helpful. I checked FileTools package quickly and couldn't notice anything like what I want. Anyone have any clue on name of such command if exists or any other trick that does what I want (except expecting the user to do something ^_^ so all from the writer's side please ^_^).

Generate a matrix of variables...

Asked by: selaf 15

February 23 2025

1 4

Hi, I want to generate a matrix of variables, say, something like,

n:=4:

Matrix(n, n, [[a_11, a_12, a_13, a_14], [a_12, a_22, a_23, a_24], [a_13, a_23, a_33, a_34], [a_14, a_24, a_34, a_44]]) :

How can I do it automatically for arbitrary values of n?

is(Im(x)*x = 0) gives true; is this a bug?...

Asked by: tilo rc 25

February 22 2025

0 2

is(Im(x)*x = 0);
true

Surely, Im(i)*i != 0?

Writing sinh(x)/cosh(x) as tanh(x) ...

Asked by: Kh22gh 25

February 22 2025

0 2

How can I convert sinh(x)/cosh(x) to tanh(x) ?

Looking for a double integral?...

Asked by: Alfred_F 330

February 22 2025

0 8

One of the most difficult/nice tasks from my collection of old problems:
Calculate Int(from 0 to 1)Int(from 0 to 1)[1/(1-x*y)]dxdy .

Display the revolution...

Asked by: jalal 435

February 22 2025

1 5

Hi,

I am looking to design a learning sequence on the applications of integral calculus (arc length, area under the curve, solid of revolution). The animation of the solid is not optimal because I want to display the revolution over [1,2] while maintaining a global view of the curve over [-3,3]. Thank you for your insights.

S7_Arc_Intégrale_Animation.mw

How define the PDE which contain integral with i...

Asked by: salim-barzani 1555

February 21 2025

1 10

i try find some part of solution of this kind of pde but i can't get results my openion is maybe this pde is wronge when i defined

pde.mw

Looking for Limes?...

Asked by: Alfred_F 330

February 21 2025

1 6

Let eps be a real number greater than zero. Calculate the limit lim(x-->oo)[x^(1-eps)*Integral(from x to x+1) sin(t^2)dt] .

Moderator- make different from the question is du...

Asked by: salim-barzani 1555

February 21 2025

2 1

Why you delete my question most of my equation are same but demand of the questions are different, i can make a 100 account and each time i asked by one of them, and right now most of my question taged like they dublicated but they are don't ، i am not jobles and sick to post a dublicate question, You started a riot.

How check this pde ?...

Asked by: salim-barzani 1555

February 20 2025

1 2

my solution is a little bit long which when i click on pdetest command i wait at least more than a hour but still is runing and i don't get any result and not give me error , which i don't know my result is true or not so How i can find that my pde by this solution it will be zero or not ?

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pde := diff(u(x, y, t), t)-(diff(diff(u(x, y, t), `$`(x, 4))+5*u(x, y, t)*(diff(u(x, y, t), `$`(x, 2)))+(5/3)*u(x, y, t)^3+5*(diff(u(x, y, t), x, y)), x))-5*u(x, y, t)*(diff(u(x, y, t), y))+5*(int(diff(u(x, y, t), `$`(y, 2)), x))-5*(diff(u(x, y, t), x))*(int(diff(u(x, y, t), y), x))

(4)

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-5*(diff(u(x, y, t), x))*(diff(diff(u(x, y, t), x), x))-5*u(x, y, t)*(diff(diff(diff(u(x, y, t), x), x), x))-5*u(x, y, t)^2*(diff(u(x, y, t), x))-5*u(x, y, t)*(diff(u(x, y, t), y))-5*(diff(u(x, y, t), x))*(int(diff(u(x, y, t), y), x)), diff(u(x, y, t), t)-(diff(diff(diff(diff(diff(u(x, y, t), x), x), x), x), x))-5*(diff(diff(diff(u(x, y, t), x), x), y))+5*(int(diff(diff(u(x, y, t), y), y), x))

(5)

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Bij := proc (i, j) options operator, arrow; (-6*p[i]-6*p[j])/(p[i]-p[j])^2 end proc

proc (i, j) options operator, arrow; (-6*p[i]-6*p[j])/(p[i]-p[j])^2 end proc

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eqf := f(x, y, t) = (-5*t*p[1]^2+y*p[1]+x)*(-5*t*p[2]^2+y*p[2]+x)-(6*(p[1]+p[2]))/(p[1]-p[2])^2

f(x, y, t) = (-5*t*p[1]^2+y*p[1]+x)*(-5*t*p[2]^2+y*p[2]+x)-6*(p[1]+p[2])/(p[1]-p[2])^2

(10)

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eq17 := u(x, y, t) = 6*(diff(diff(f(x, y, t), x), x))/f(x, y, t)-6*(diff(f(x, y, t), x))^2/f(x, y, t)^2

u(x, y, t) = 6*(diff(diff(f(x, y, t), x), x))/f(x, y, t)-6*(diff(f(x, y, t), x))^2/f(x, y, t)^2

(11)

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u(x, y, t) = 12/((-5*t*p[1]^2+y*p[1]+x)*(-5*t*p[2]^2+y*p[2]+x)-6*(p[1]+p[2])/(p[1]-p[2])^2)-6*(-5*t*p[1]^2-5*t*p[2]^2+y*p[1]+y*p[2]+2*x)^2/((-5*t*p[1]^2+y*p[1]+x)*(-5*t*p[2]^2+y*p[2]+x)-6*(p[1]+p[2])/(p[1]-p[2])^2)^2

(12)

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Download test.mw

animate the Riemann sum...

Asked by: jalal 435

February 20 2025

1 1

Hi,

I'm looking to animate the Riemann sum only on the interval [0,2], while keeping a global view of the curve (G). I tried the background option, but without success. Any ideas? Thanks!

S7_Riemann_Animation_Aire.mw

how to plot 2d: x=a, y=b of which a and b are rand...

Asked by: Aixleft math 120

February 19 2025

1 12

Hi. How to plot the 2d output like this? I don't know how to declare "a" and "b" random constant?
The pair of equations x = a and y = b graphically represents lines which are, a. parallel , b. intersecting at (b, a), c. coincident, d. intersecting at (a, b)