Unanswered Questions

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Hello every body

I have a plot that contains two curve. I need to chracterize the curves with `min(D_{T})` and `max(D_{E})`. Is it possible to write legend of plot such that when include it in latex file,  T and E be presented in indices?

"The account type or email address or password is incorrect."

None of those things is true. Using those same credentials, I am able to log in to Maple Cloud in my office but not from home. 

Has anyone else had this problem or know of a solution?


Running Maple 2017 in office on Windows 7 and at home on Windows 10.

Office copy is through a site license purchased by my university. Home copy is a personal home-use copy obtained through the Maple Adoption program.

I am attempting to build a text field at the bottom of this worksheet MathApps-ResistorsMark.mw  that asks users for the resistance.

I am hoping to have the value of the text field evaluated using the Module() at the bottom of the startup code, for use as a question within MapleTA.  For some reason I can get the code to work for a slider, but not a textbox.

I have limited knowledge about startup code.

Notice: I will be removing the resistance from the diagram for students after I know it works.

I appreciate any help that can be offered.

Dear Maple users,

I am solving a system of linear equations Ax=b where A is a matrix (243*241) which contains a rational polynomial of unknown "kappa" along with floating numbers. As suggested in some other posts I am using Linear algebra package with the LinearSolve command and option "solve" to find out unknown vector x. b is a vector having entries zero and 1. The system is such that two equations are redundant but it is difficult to recognise which two are redundant and hence for the time being I am keeping them in the matrix. (For a known value of kappa (say kappa=2) I have checked that two equations are redundant.) For the reference, the matrix and the right-hand vector b is attached as text.

There are two issues

1) Maple takes very long time (12 hours and so) to get x=b\A;

2) The result is a long expression i.e.  x[i] is a rational polynomial in kappa; a very long rational polynomial which I am importing as a text. I am not sure if maple exports all terms in the polynomial as for the different value of kappa I see Ax-b >0. 

How can I overcome this problem? Any help will be greatly appreciated. 



as screen shot shown i just was wondering if the mechanic is available my engine dispatched again so um i guess i can pay in reputation points or food stamps, i just dont see why engine would desire either tho being an artificial entity and all. i mean its not like you need to eat.

ode1a := diff(y1(tt),tt) = round(rhs(odeparm1[1][1]))*y1(tt) + round(rhs(odeparm1[1][2]))*y2(tt) + round(rhs(odeparm1[1][3]))*y3(tt);
ode2a := diff(y2(tt),tt) = round(rhs(odeparm1[1][4]))*y1(tt) + round(rhs(odeparm1[1][5]))*y2(tt) + round(rhs(odeparm1[1][6]))*y3(tt);
ode3a := diff(y3(tt),tt) = round(rhs(odeparm1[1][7]))*y1(tt) + round(rhs(odeparm1[1][8]))*y2(tt) + round(rhs(odeparm1[1][9]))*y3(tt);
sys := subs(y3(tt)=1,[ode1a,ode2a]);
print(DEplot(sys, [y1(tt), y2(tt)], tt = 0 .. 16, y1 = -16 .. 16, y2 = -16 .. 16, color = magnitude, title = `Stable Limit Cycles`, arrows = curve, dirfield = 800, axes = none));


how to mirror the vector field graph mathematically?

mirror the graph about x=0 this line,

so that the graph looked flip

i find curl can do, but how to do ?


SetCoordinates('cartesian'[x(t), y(t), z(t)]);
Curl((x(t),y(t),z(t)),(Diff(x(t),t) - a11*x(t) - a12*y(t) - a13*z(t),Diff(x(t),t) - a21*x(t) - a22*y(t) - a23*z(t),Diff(x(t),t) - a31*x(t) - a32*y(t) - a33*z(t)));
Error, (in VectorCalculus:-SetCoordinates) coordinate system `cartesian[x(t), y(t), z(t)]` does not exist
Error, (in Vector) dimension parameter is required for this form of initializer


Hi quick question.  When I am writing in maple 2D input the next line seems to add a space and I have to manually go and take the spaces out.  Is there a quick fix for this?  

Thank you.

Hello everybody

I'm using discrete distributions from the Statistics package and I found a rather strange result.

In short the theoritical values of some statistics of a NegativeBinomial(1, P) Random Variable (P being the probability of success equal to 1e-4) are correctly computed, but their empirical estimators computed from a sample of this RV are roughly wrong.

For NegativeBinomial(1, P) is similar to Geometric(P) I asked Maple to compute the theoritical values of some statistics of Geometric(P) and next to assess their empirical values from a sample of Geometric(P).
Some discrepancies still remain but they can be explained by statistical fluctuations.

Could you please look to the attached file (an error on my part is still possible) and help me to fix this ?

Thanks in advance

PS : the histogram of Sample(NegativeBinomial(K, P), AnySizeYouWant) is obviously wrong (it should look like a decreasing exponential) 


Download NegativeBinomial.mw

I have recently reinstalled the MapleSim 6.4 but the probe windows do not appeaar anymore.

The image below shows that there are 3 probes (none are disabled) and when I run the simulation nothing happens.,

seq(alias(a[i] = RootOf(_Z1^6-3*_Z1^2-2*_Z1+11, index = i)), i = 1..6):

ee := a[1]*a[5]+a[2]*a[6]+a[3]*a[4];

                       3.999999999 + 0. I


                  3.139680582 - 1.737673929 I

I wasn't able to figure out what it depends on, but evala(ee) doesn't always do the same thing. If I don't evaluate evalf(ee) first, then most times I get the correct result evala(ee)=4.

This is in Maple 2017.2, system="X86 64 WINDOWS", wordsize=64.


aa := tan(Pi/11)^2;
bb := RootOf(_Z^5-55*_Z^4+330*_Z^3-462*_Z^2+165*_Z-11, index = 1); # bb = aa
ee := (exp(-Pi-I*Pi*aa/bb))^(1+I);

seq((proc() try timelimit(k, signum(Re(ee)-1/k)) catch: lprint(lastexception) end try end proc)(),
    k = 1..10);

`shake/shake`, "time expired"
`expand/sin`, "time expired"
`evalr/tan`, "time expired"
sdmp:-mul, "time expired"
                        1, 1, 1, 1, 1, 1

An explanation: aa/bb=1, so, as we know from here, ee=exp(-2*Pi), and ee is tricky to evaluate numerically. Normally signum(Re(ee)-1/5) just seems to hang indefinitely, which is not the worst thing it could do. But after one of the timelimit interrupts (or after clicking "Interrupt the current operation"), something breaks, and Maple starts returning wrong values.

This is in Maple 2017.2, system="X86 64 WINDOWS", wordsize=64.

Also, is there any way to clear the cached values so that this computation can be repeated without doing restart?


I have encountered bug in factors/fsolve while working with 19-th degree polynomial: 




fsolve(T,fulldigits); # <-- completes without issues

factors(T);           # <-- freezes with log:
fsolve: ill-conditioned polynom of degree 19, with 0(0) given roots
fsolve: 1th root found in 9 iters at 165 Digits
fsolve: 2th root found in 11 iters at 164 Digits
fsolve: 3th root found in 11 iters at 165 Digits
fsolve: 4th root found in 10 iters at 174 Digits
fsolve: 5th root found in 10 iters at 167 Digits
fsolve: 6th root found in 11 iters at 168 Digits
fsolve: 7th root found in 11 iters at 174 Digits
fsolve: 8th root found in 11 iters at 170 Digits
fsolve: 9th root found in 11 iters at 181 Digits
fsolve: 10th root found in 11 iters at 172 Digits
fsolve: 11th root found in 12 iters at 175 Digits
fsolve: 12th root found in 11 iters at 182 Digits
fsolve: 14th root found in 14 iters at 177 Digits
fsolve: 15th root found in 10 iters at 176 Digits
fsolve: 16th root found in 11 iters at 173 Digits
Warning,  computation interrupted


The most interesting thing is that standalone 'fsolve' finishes fine, but 'factors' freezes in 'fsolve:-polyill' on the same polynomial.

My system is: Windows 7 x64, Maple 2017.0.

Would appreciate any help on how to avoid the issue with 'factors'.

ode1a := diff(y1(tt), tt) = 1.342398800*10^5*y1(tt)+89591.20000*y2(tt)+44647.44000*y3(tt);
ode2a := diff(y2(tt), tt) = 89591.20000*y1(tt)+89803.24000*y2(tt)+44901.60000*y3(tt);
ode3a := diff(y3(tt), tt) = 44647.44000*y1(tt)+44901.60000*y2(tt)+44859.24000*y3(tt);

would like to find the origin eigenstate before it collapse to eigenvalues

how to apply ricci flow in this situation?

i find help file , and can not find some relationship between this application and inputs of ricci related function

which functions in maple can help to find origin of eigenstate

I have a few "regular practices" on the interface that i want to implement into conjecturing automata, and i would really really be super appreciative if i can interface it with simon's/maplsoft's inverse symbollic calculator, the only problem really is  the HTTP aspect is going  to ( im assuming) need certain information only known to the people who brought the symbolliic calc online. So thats my  question / request for help

From clues:
a1 := subs(y=n,1/y!*x^y); # diff make it equal to the left term
a2 := subs(y=n-1,1/y!*x^y);
simplify(factor(a1 - a2));
To find limit of below
nterm := sum(tanh(product(sum(kk, kk=1..jj),jj=1..y))*1/y!*x^y, y=n..n);
n2term := sum(tanh(product(sum(kk, kk=1..jj),jj=1..y))*1/y!*x^y, y=(n+1)..(n+1));
simplify(factor(n2term - nterm));
simplify(limit((subs(x=x+h, n2term)-n2term)/h, h=0)) = nterm;
question is to find a limit make n2term equal nterm after calculation
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