For the last 24hrs or so I have found it almost impossible to upload worksheet files in response to questions.

My usual approach is

Big green up-arrow:
(uploader pop-up appears)

Browse files

(this still works)

Upload file

This is the problem step - I generally just get "waiting for Mapleprimes" in my browser's annunciator box: and I wait, and wait, (as in >5 minutes) and still this step does not complete. Just to be annoying, every once in a while the file will upload as normal, such but success is now the exception

I'm seeing the same issue in Firefox 45.0.2 and Chrome 50.0.2661.75mon Win 7, 64-bit.

Anyone else seeing the same issue?

Dear Maple researchers

I have a problem in solving a system of odes that resulted from discretizing, in space variable, method of lines (MOL).

The basic idea of this code is constructed from the following paper:

http://www.sciencedirect.com/science/article/pii/S0096300313008060

If kindly is possible, please tell me whas the solution of this problem.

With kin dregards,

Emran Tohidi.

My codes is here:

> restart;
> with(orthopoly);
print(`output redirected...`); # input placeholder
> N := 4; Digits := 20;
print(`output redirected...`); # input placeholder

> A := -1; B := 1; rho := 3/4;
> g1 := proc (t) options operator, arrow; 1/2+(1/2)*tanh((1/2)*(A-(2*rho-1)*t/sqrt(2))/sqrt(2)) end proc; g2 := proc (t) options operator, arrow; 1/2+(1/2)*tanh((1/2)*(B-(2*rho-1)*t/sqrt(2))/sqrt(2)) end proc;
print(`output redirected...`); # input placeholder
> f := proc (x) options operator, arrow; 1/2+(1/2)*tanh((1/2)*x/sqrt(2)) end proc;
print(`output redirected...`); # input placeholder
> uexact := proc (x, t) options operator, arrow; 1/2+(1/2)*tanh((1/2)*(x-(2*rho-1)*t/sqrt(2))/sqrt(2)) end proc;
print(`output redirected...`); # input placeholder
> basiceq := simplify(diff(uexact(x, t), `$`(t, 1))-(diff(uexact(x, t), `$`(x, 2)))+uexact(x, t)*(1-uexact(x, t))*(rho-uexact(x, t)));
print(`output redirected...`); # input placeholder
                                      0
> alpha := 0; beta := 0; pol := P(N-1, alpha+1, beta+1, x); pol := unapply(pol, x); dpol := simplify(diff(pol(x), x)); dpol := unapply(dpol, x);
print(`output redirected...`); # input placeholder
> nodes := fsolve(P(N-1, alpha+1, beta+1, x));
%;
> xx[0] := -1;
> for i to N-1 do xx[i] := nodes[i] end do;
print(`output redirected...`); # input placeholder
> xx[N] := 1;
> for k from 0 to N do h[k] := 2^(alpha+beta+1)*GAMMA(k+alpha+1)*GAMMA(k+beta+1)/((2*k+alpha+beta+1)*GAMMA(k+1)*GAMMA(k+alpha+beta+1)) end do;
print(`output redirected...`); # input placeholder
> w[0] := 2^(alpha+beta+1)*(beta+1)*GAMMA(beta+1)^2*GAMMA(N)*GAMMA(N+alpha+1)/(GAMMA(N+beta+1)*GAMMA(N+alpha+beta+2));
print(`output redirected...`); # input placeholder
> for jj to N-1 do w[jj] := 2^(alpha+beta+3)*GAMMA(N+alpha+1)*GAMMA(N+beta+1)/((1-xx[jj]^2)^2*dpol(xx[jj])^2*factorial(N-1)*GAMMA(N+alpha+beta+2)) end do;
print(`output redirected...`); # input placeholder
> w[N] := 2^(alpha+beta+1)*(alpha+1)*GAMMA(alpha+1)^2*GAMMA(N)*GAMMA(N+beta+1)/(GAMMA(N+alpha+1)*GAMMA(N+alpha+beta+2));
print(`output redirected...`); # input placeholder
> for j from 0 to N do dpoly1[j] := simplify(diff(P(j, alpha, beta, x), `$`(x, 1))); dpoly1[j] := unapply(dpoly1[j], x); dpoly2[j] := simplify(diff(P(j, alpha, beta, x), `$`(x, 2))); dpoly2[j] := unapply(dpoly2[j], x) end do;
print(`output redirected...`); # input placeholder
print(??); # input placeholder
> for n to N-1 do for i from 0 to N do BB[n, i] := sum(P(jjj, alpha, beta, xx[jjj])*dpoly2[jjj](xx[n])*w[i]/h[jjj], jjj = 0 .. N) end do end do;
> for n to N-1 do d[n] := BB[n, 0]*g1(t)+BB[n, N]*g2(t); d[n] := unapply(d[n], t) end do;
print(`output redirected...`); # input placeholder
> for nn to N-1 do F[nn] := simplify(sum(BB[nn, ii]*u[ii](t), ii = 1 .. N-1)+u[nn](t)*(1-u[nn](t))*(rho-u[nn](t))+d[nn](t)); F[nn] := unapply(F[nn], t) end do;
print(`output redirected...`); # input placeholder
> sys1 := [seq(d*u[q](t)/dt = F[q](t), q = 1 .. N-1)];
print(`output redirected...`); # input placeholder
[d u[1](t)                                                                
[--------- = 40.708333333333333334 u[1](t) + 52.190476190476190476 u[2](t)
[   dt                                                                    

                                                                  2          3
   + 39.958333333333333334 u[3](t) - 1.7500000000000000000 u[1](t)  + u[1](t)

   + 7.3392857142857142858

   - 3.6696428571428571429 tanh(0.35355339059327376220

   + 0.12500000000000000000 t) - 3.6696428571428571429 tanh(
                                                     d u[2](t)   
-0.35355339059327376220 + 0.12500000000000000000 t), --------- =
                                                        dt       
-20.416666666666666667 u[1](t) - 25.916666666666666667 u[2](t)

                                                                  2          3
   - 20.416666666666666667 u[3](t) - 1.7500000000000000000 u[2](t)  + u[2](t)

   - 3.7500000000000000000

   + 1.8750000000000000000 tanh(0.35355339059327376220

   + 0.12500000000000000000 t) + 1.8750000000000000000 tanh(
                                                     d u[3](t)                
-0.35355339059327376220 + 0.12500000000000000000 t), --------- = 29.458333333\
                                                        dt                    

  333333333 u[1](t) + 38.476190476190476190 u[2](t)

                                                                  2          3
   + 30.208333333333333333 u[3](t) - 1.7500000000000000000 u[3](t)  + u[3](t)

   + 5.4107142857142857144

   - 2.7053571428571428572 tanh(0.35355339059327376220

   + 0.12500000000000000000 t) - 2.7053571428571428572 tanh(
                                                   ]
-0.35355339059327376220 + 0.12500000000000000000 t)]
                                                   ]
> ics := seq(u[qq](0) = evalf(f(xx[qq])), qq = 1 .. N-1);
print(`output redirected...`); # input placeholder
    u[1](0) = 0.38629570659055483825, u[2](0) = 0.50000000000000000000,

      u[3](0) = 0.61370429340944516175
> dsolve([sys1, ics], numeic);
%;
Error, (in dsolve) invalid input: `PDEtools/sdsolve` expects its 1st argument, SYS, to be of type {set({`<>`, `=`, algebraic}), list({`<>`, `=`, algebraic})}, but received [[d*u[1](t)/dt = (20354166666666666667/500000000000000000)*u[1](t)+(13047619047619047619/250000000000000000)*u[2](t)+(19979166666666666667/500000000000000000)*u[3](t)-(7/4)*u[1](t)^2+u[1](t)^3+36696428571428571429/5000000000000000000-(36696428571428571429/10000000000000000000)*tanh(1767766952966368811/5000000000000000000+(1/8)*t)-(36696428571428571429/10000000000000000000)*tanh(-1767766952966368811/5000000000000000000+(1/8)*t), d*u[2](t)/dt = -(20416666666666666667/1000000...

I am currently working on FDM ,i have 2 coupled nonlinear pde ,i need help in solving these equation using maple code.

> restart:

> alias(f=f(tau,eta), theta=theta(tau,eta));

>

> PDE1:=S*diff(f,tau,eta)=eta^2*diff(f,eta)^2+(6*eta^2-2*f*eta)*diff(f,eta)+(6*eta^3-f*eta)*diff(f,eta,eta)-eta^4*diff(f,eta,eta,eta);

> PDE2:=eta^4*diff(theta,eta,eta)+2*eta^3*diff(theta,eta)-Pr*(f*eta^2*diff(theta,eta)+S*diff(theta,tau))=0;

The code I write is properly indented.  The operation of pasting it here strips the white space and makes it hard for the reader to comprehend the structure. Manually restoring the appropriate indentation is doable but tedious, made more so because the characters we see here are in a variable width font.  The rationale might be that, given a variable width font the indentation is going to be inconsistent, but that isn't the case if the preformatted style is used, which I do, for code.

Is there any way to turn off the white space stripping?  Presumably this is some ridiculous xml-based processing feature.

I have checked many Maple pages and I found nowhere the answer to this question.

EQ:= s^2-4*s+1=3;

I need to print the following statement:

The Equation Is: EQ

I need the equation to appear where EQ is.

Thank you guys!

I appreciate it.

I have the following problem : plotting with the squareroot function somehow stops showing the whole graph as soon as the range of the input allows values less than -10, I have attached two pictures that show the transition:

This is still fine:

But here is an example where the graph is cropped:

How can I change this to get the whole graph ? Thanks a lot for your help !!

Is there a Maple function that given a set of substitutions in form object=set of substitute objects produces a sequence of sets, each a product of substitution from the next, remove repetitions. An example:

Hi I'm not really sure how to phrase this but I'm doing projectile motion and I'm try to graph the solutions for v_0 by theta_0.

hi .why matrix a dont create?

bot.mw

Download bot.mw

I want to solve system of non linear odes numerically.

I encounter following error

Error, (in dsolve/numeric/bvp) cannot determine a suitable initial profile, please specify an approximate initial solution

how to correct it

regards

In workbook mode I use the Insert>>Paragaph>>Before Cursor to create a text block. I just want to type text into this block by way of comments on what preceded/follows. However, when I type parentheses or <> of (I expect) other stuff that Maple recognises as being parts of mathematical expressions Maple switches to italic and bold and starts generally interefering with my text. In the case of my title I get the result in the picture below. Is there any way to stop Maple doing this so I can type text?

How I can solve it ? If I want a solution dependent of a. With fsolve? But how?

-x³+ax²-lnx=0
 

Hello,

I'm working in a project where I use the Java Open Maple library. I need to evaluate a procedure but with a very large number. In the function engine.newNumeric() the only large option is a long which is not enough for me. I use Java BigInteger class to represent my very large numbers. Any suggestions that might help is very welcomed!

Thank you

I am trying to write a procedure that implements Karmarkar's algorithm for solving linear programming problems.

I am getting a parsing error and I am not sure why. Each of the command in the procedure are working the way I want them to but there is something wrong with the loop controls. The code is attached below:

with(LinearAlgebra);

print(??); # input placeholder
Karmarkar:= proc(A,c)

     n:=ColumnDimension(A);

     x:=ZeroVector(n);

     y:=Vector(n,1/(n));

     r:=1/(sqrt(n*(n-1)));

     for i from 1 to nops(NullSpace(A))do

          x:=x+NullSpace(A)[i];

     end do;

     C:=1.0;

     while C>0.0001 do ;

          Diag := DiagonalMatrix(x/Norm(x, 1));

          B := `<,>`(A.Diag, Vector[row](n, 1));

          p := (IdentityMatrix(n)-Transpose(B).MatrixInverse(B.Transpose(B)).B).Transpose(c.Diag);

          p:=evalf(p/(Norm(p,2)));

          y:=y-0.9*r*p;

          x_new:=evalf((Diag . y)/((Vector[row](n,1) . (Diag . y))));

          C:=evalf((c . x_new-c . x)/(c . x));

          if C>0.0001 then

               x_new:=x;

          end if;

      end do;

end proc;

Any ideas on how to fix this?

I'm trying to solve a system of two differential equations of the second order in Maple. I set it up as a system of four differential equations of the first order, but after calling for the solution, all I get back is what I entered in without receiving a solution of any sort. What do I need to fix?

Here's what I did:

_________________________________________________

> with(plots);
print(`output redirected...`); # input placeholder

> m := 0.46e-1; d := 0.42e-1; v := 60; alpha0 := 12; g := 9.81; pa := 1.205; cd := .2; n := 100; omega := 2*Pi*(1/60);
                            
> p := 6*m/(Pi*d^3);

> k1 := (3/4)*cd*pa/(d*p); k2 := (3/8)*omega*pa/p;
                                        
> gl1 := vx(t) = diff(x(t), t);                   
> gl2 := vy(t) = diff(y(t), t);
                              
> gl3 := diff(vx(t), t) = -k1*vx(t)*(vx(t)^2+vy(t)^2)^(1/2)-k2*vy(t);
 
> gl4 := diff(vy(t), t) = -g-k1*vy(t)*(vx(t)^2+vy(t)^2)^(1/2)+k2*vy(t);


> init1 := x(0) = 0;
> init2 := y(0) = 0;
> init3 := vx(0) = v*cos((1/15)*Pi);                              
> init4 := vy(0) = v*sin((1/15)*Pi);

> sol; dsolve({gl1, gl2, gl3, gl4, init1, init2, init3, init4}, {vx(t), vy(t), x(t), y(t)}, type = numeric);

> sol(.1);
                            sol(0.1)

> odeplot(sol, t, x(t), t, y(t), t = 0 .. 1);
                   Error, (in plots/odeplot) input is not a valid dsolve/numeric solution


____________________________________________________________________________

After calling for the solution at t=0.1, I don't get anything back. I also tried plotting the solution, but then I receive an error message.