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Dear, I am facing a problem which I run the attached file it this answer [Length of output exceeds limit of 1000000]. Please help to overcome this problem.

ytsf3.mw

With my best regards and sincerely.

Govt. Degree College Taxila

Hi,

I am experiencing some problems with the plot3d command. It does not return a nice 3d-graph, but just a bunch of dashed lines. I have entered something like this:

with(plots):

plot3d(x*y,x=-1..1,y=-1..1);

I am using maple 17 on windows 7

Thanks in advance.

I can't solve this problem, can someone explain me whats worng and how to fix it, here is what i've done:

with(plots);
with(DEtools);
sist := diff(x1(t), t) = -4*x1(t)+x2(t), diff(x2(t), t) = -x1(t)+7*x2(t);
    d                             d                          
   --- x1(t) = -4 x1(t) + x2(t), --- x2(t) = -x1(t) + 7 x2(t)
    dt                            dt                         


condi := [x1(0) = 0, x2(0) = 3], [x1(0) = 2, x2(0) = 1], [x1(0) = 7, x2(0) = 9];
        [x1(0) = 0, x2(0) = 3], [x1(0) = 2, x2(0) = 1],

          [x1(0) = 7, x2(0) = 9]
for i to 3 do sol[i] := dsolve({sist, condi[i]}, {x1(t), x2(t)}, numeric); gra := odeplot(sol[i], [x1(t), t], t = -1 .. 1); display(gra) end do;

Here is a simple example to explain my problem:

I would like to have a break after the first graph and with return

the loop shoul continue to the next and so on.

Thank you for your help!

 

Test:=proc()

    plot(x^j,x=-2..2):

end proc:

for j from 1 to 3 do

   Test()

end do;

Hello,

I'm trying to calculate and export a huge "Strategy-Matrix". The calculation works in a smaller version with less possible strategies. For this version I use a specialised simulation-PC with enough memory (that was my problem using my own PC). But now I've got this error massage ("Kernel connection has been lost. You should save this worksheet and restart Maple. Executing commands in Maple requires a connection to the Maple kernel. Firewalls have been known to cause problems with kernel connections in Maple. Please ensure that any firewall software is configured to allow Maple to create connections to the kernel. Consult the FAQ for more information.")

The firewall should not be the problem. Below the code. num_Strat is 63001. 

Thank you in advance for your help.

 

m_Gi:= Matrix(num_Strat, num_Strat):

for t from 1 by 1 to num_Strat
do
Digits:= 5:
v_h2:= evalf((-(24/17)* v_pEi[t]^2)*v_h1 + (v_pEi[t]*(-(128/51)*v_pKi[t]+980/51))*v_h1+ v_pEi[t]*((40/51)*v_pKj+(15/17)*v_pEj)-((110/51)*v_pKi[t]^2)*v_h1 + v_pKi[t]*((55/51)*v_pKj+1220/51*v_h1+(10/17)*v_pEj)):
m_Gi(..,t):= v_h2:
end do:
ExportMatrix(TestMatrixNK, m_Gi):

I have a problem when using units in a solve

restart;
Following is from the assignment
Q := 20*Unit('m')^3/Unit('s');

I__e := 0.2e-1;

B := 2*Unit('m');

k := 0.3e-2*Unit('m');

g := 9.82*Unit('m')/Unit('s')^2;

Mannings number
M := 8.1*g^(1/2)/k^(1/6);
A := y*B;


R := y*B/(B+2*y);


V := M*R^(2/3)*sqrt(I__e);
y__0 := solve(Q = V*A, y);
=
/ (5/3)\// /
\0.002644870772 Units:-Unit('m') / \RootOf\
(8/3) 3 (5/3)
-625 Units:-Unit('m') + 5000000 _Z Units:-Unit('m')

5 \ \
+ 1890451531 _Z Units:-Unit('m')/^2/

 

Hope you can use this.. It's the first time I ask a question on this site...

Could anyone please hepl me? I have the following system

e1 := exp(F(r)/phi_0)*L*A(r) = (1/2)*(2*(diff(A(r), r, r))*B(r)*A(r)*r*C(r)+2*B(r)*A(r)*(diff(A(r), r))*(diff(C(r), r))*r-(diff(A(r), r))^2*B(r)*r*C(r)-(diff(A(r), r))*(diff(B(r), r))*A(r)*r*C(r)+4*B(r)*A(r)*(diff(A(r), r))*C(r))/(B(r)^2*A(r)*r*C(r));
e2 := alpha*(diff(F(r), r, r))+(alpha^2+omega)*(diff(F(r), r))^2+(1/4)*(4*(diff(C(r), r, r))*B(r)*A(r)^2*C(r)*r+2*(diff(A(r), r, r))*A(r)*B(r)*r*C(r)^2-2*B(r)*A(r)^2*(diff(C(r), r))^2*r-(diff(A(r), r))^2*B(r)*r*C(r)^2-2*A(r)^2*C(r)*(diff(C(r), r))*(diff(B(r), r))*r-(diff(A(r), r))*(diff(B(r), r))*A(r)*r*C(r)^2+8*B(r)*A(r)^2*C(r)*(diff(C(r), r))-4*A(r)^2*C(r)^2*(diff(B(r), r)))/(r*A(r)^2*B(r)*C(r)^2)-(1/4)*(2*(diff(A(r), r, r))*B(r)*A(r)*r*C(r)+2*B(r)*A(r)*(diff(A(r), r))*(diff(C(r), r))*r-(diff(A(r), r))^2*B(r)*r*C(r)-(diff(A(r), r))*(diff(B(r), r))*A(r)*r*C(r)+4*B(r)*A(r)*(diff(A(r), r))*C(r))/(B(r)*A(r)^2*r*C(r)) = 0;
e3 := (1/4)*(-2*(diff(C(r), r, r))*B(r)*A(r)*r^2-B(r)*(diff(A(r), r))*(diff(C(r), r))*r^2+A(r)*(diff(C(r), r))*(diff(B(r), r))*r^2-8*B(r)*A(r)*(diff(C(r), r))*r-2*B(r)*(diff(A(r), r))*C(r)*r+2*A(r)*C(r)*(diff(B(r), r))*r+4*B(r)^2*A(r)-4*B(r)*A(r)*C(r))/(B(r)^2*A(r)) = -(1/4)*(2*(diff(A(r), r, r))*B(r)*A(r)*r*C(r)+2*B(r)*A(r)*(diff(A(r), r))*(diff(C(r), r))*r-(diff(A(r), r))^2*B(r)*r*C(r)-(diff(A(r), r))*(diff(B(r), r))*A(r)*r*C(r)+4*B(r)*A(r)*(diff(A(r), r))*C(r))*r/(B(r)^2*A(r)^2);
e4 := -(alpha^2+2*omega)*(diff(F(r), r))*(-(1/2)*(-(diff(A(r), r))*B(r)*r^4*C(r)^2-A(r)*(diff(B(r), r))*r^4*C(r)^2-4*A(r)*B(r)*r^3*C(r)^2-2*A(r)*B(r)*r^4*C(r)*(diff(C(r), r)))/(A(r)*B(r)*r^4*C(r)^2)-(diff(B(r), r))/B(r)+(diff(F(r), r, r))/(diff(F(r), r))+alpha*(diff(F(r), r)))/B(r) = -exp(F(r)/phi_0)*V_0*(alpha-1/phi_0);

phi_0 := -alpha/(2*alpha^2+2*omega); L := V_0*(1-(alpha-1/phi_0)*alpha/(3*alpha^2+2*omega)); V_0 := -lambda*exp(-fc/phi_0); fc := ln((4*alpha^2+2*omega)/(G_0*(3*alpha^2+2*omega)))/alpha; m := (2/(1+g))^(1/2); n := g*(2/(1+g))^(1/2); P := (G_0*(3*alpha^2+2*omega)/(4*alpha^2+2*omega))^(-2*alpha/(n-m)); eta := 1.4*G_0*Ms*(2/(1+g))^(-1/2)/c^2; g := 1-alpha^2/(2*alpha^2+omega);

omega := -10^5; alpha := 1; G_0 := 6.67*10^(-11); lambda := 10^(-52); c := 2.9*10^8; Ms := 1.9*10^30;
ri := evalf(1000*eta);

ics := A(2.109660445*10^6) = 1, (D(A))(2.109660445*10^6) = 2.370091128*10^(-15)*sqrt(2)*sqrt(99998)*sqrt(199997), B(2.109660445*10^6) = 1, C(2.109660445*10^6) = 1, (D(C))(2.109660445*10^6) = 4.740182256*10^(-15)*(1-(99999/19999300006)*sqrt(2)*sqrt(99998)*sqrt(199997))*(1-1.000017501*10^(-8)*sqrt(2)*sqrt(99998)*sqrt(199997))^(-(99999/19999300006)*sqrt(2)*sqrt(99998)*sqrt(199997))*sqrt(2)*sqrt(99998)*sqrt(199997), f(2.109660445*10^6) = 23.43081116, (D(f))(2.109660445*10^6) = 4.749681180*10^(-15):

eta:=2109.660445: sys:=e1,e2,e3,e4; vars:=[A(r),B(r),C(r),F(r)];

dsn3 := dsolve([sys, ics], numeric, vars, range = 3*eta .. 50*eta);

Results in

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

Setting f(r)=Const,V_0=0 which is a physically relevant case, results in

Error, (in simplify/normal) numeric exception: division by zero

I suugest the problem is that the equation contain sqared derivatives, hence there are several solution branches corresponding to different signs of square root. Maple chooses the singular branch. How can I force it to choose another branch or calculete all of them?

Thanks in advance..





Hello again,

for a paper I need to cipher and decipher with the standard RSA-procedure.
My problem is, that my numbers are really large.

As normally it's just, given a public key (e,N) and a private key (d,p,q), p,q are primes, and the plaintext:

encrypt: b^e mod N = c

decrypt: c^d mod N = b

That works cause ed = 1 mod (p-1)(q-1) (Euler's Phi-Function) and gcd(e,N)=1

 

With little numbers thats no problem. But increasing e and N, i thought using the powmod function will help:

b&^e mod N = c but

c&^d mod N <> b.

So it doesnt work anymore and I really dont get why...

 

thanks for help, I'm really lost here..

I have been Maple  18 with no problem. Then, today, the  "=" symbol and  "+" symbol don't work.  Does anyone know what to do about this?

 

Dear mapleprimes users,

I have a problem concerning this function:

Naief := proc(A::integer,B::integer, p::posint)
local x, a:= A mod p, b:= B mod p;

 for x from 1 to p-1 do
    if a^x mod p = b then return x end if
end do;
print(¨No solution.¨)

end proc

It works fine for what it should do, finding x for a^x = b mod p by inserting x from 1 to p-1 until it finds an
apprioperate x.

My problem is concerning its computation time, which I like to calculate with:

Codetools:- Usage(Naief(a,b,p), output = [cputime], quiet, iterations= 2^12)

The problem is that keeps repeating

alot even when a,b and p are immensely huge. I don`t know how to fix it, because I need real CPUtimes which increase
a,b and p increase. I get the idea that the values of the CPUtime are not realistic.

 

Thanks for the help!

 

 

 

Hi I'm new to maple

I wanted to use dsolve to solve and equation but instead of getting an answer, maple returns an integration.

What could the promblem be?

Thanks

Hello, I am new user of Maple and I have simple problem. I have different results after pasting and typing text. Can you help me?different signs

Hi all,

I'm currently writing a code to solve the equations for a gravitational collapse of a star numerically. I'm using two dimensional Arrays for most of the physical quantities in my finite difference equations, with one index for the spatial dimension (I'm only considering spherically symmetric collapses) and one time index. I wrote two nested loops, where the inner one solves the equations from the centre of the star to the surface (with the exception of one quantitiy, where I have to integrate the other way around) and the outer loop advances the Arrays in time. My problem is, that Maple doesn't seems to evaluate the two dimensional Arrays. Instead for inserting the appropriate value for e.g. A[3,2], Maple just keeps on using A[3,2] which messes up some formulas, since I have to take roots of the numbers. At least that is what seems to be going on when I'm trying to debug the relevant part of the code and I check for the values, with whicih Maple calculates. I'm also using a one dimensional Array to store the timesteps, I'm using in the code and Maple doesn't seem to have problems evaluating them. Is anybody familiar with this problem? Does Maple have trouble with multidimensional Arrays in loops or have I just messed up my code? I have uploaded my code (I hope it worked). I apologize for my code being messy, but it's the first time I'm working with Maple and using numerical methods. The part which troubles me is labeled "# actual code".

Thank you all.

Oppenheimer-Snyder_Maple_3.mw

files.mw

From art of problem solving ws: "Jamal wants to save 30 files onto disks, each with 1.44 MB space. 3 of the files take up 0.8 MB, 12 of the files take up 0.7 MB, and the rest take up 0.4 MB. It is not possible to split a file onto 2 different disks. What is the smallest number of disks needed to store all 30 files?"

The answer is 13: 3*[0.4,0.8]+6*[0.7,0.7]+4*[0.4,0.4,0.4]

How to accomplish this in maple? my attempt doesnt work, unsurprisingly...

Dear Maple experts,

I want to solve the following problem with Maple. I appreciate if you can help.

 

n:=1+(2/Pi)*evalf(Int((x*0.187549975)/(x2-10.692), x=0..infinity));

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