Unanswered Questions

This page lists MaplePrimes questions that have not yet received an answer

 

how to call matlab to run k means on the data and

how to show which circle do the row of data belong to?

Hello,

 

  I have a complicated task. Suppose there is a file, its content is

1

A    3
0.8 0.2

0.6 0.3

0.5 0.4
****
2
A   3

0.8 0.2

0.6 0.3

0.5 0.4

****

 

  I want to read the file for each line, and store the content in each variable, e.g. "S" and 3 for two different variables, respectively. 

By using 

Nn:=readline("file");
Nn2:=readline("file");
Nn3:=readline("file");

parse(Nn);

parse(Nn2);

 

For N2, it does not work "Error, incorrect syntax in parse: unexpected number (near 6-th character of parsed string)"

 

How to read such a file properly including varies of content? Thanks a lot!

 

 

The help of maple software is not so clear , and I cant understand the exact way which leads to exporting a matrix from maple to matlab. more precisely how I can link between maple and matlab .

would you please with an example show me the rule.

guys ,

in a differential equation i want to expand its variable, but i  have some problem with it for exponential term :jadid.mw

 

 

thanks guys

 

 

The model of fixed-bed adsorption column

Fluid phase:

PDE:= diff(U(x, tau),tau)+ psi*Theta*diff(U(x, tau),x)-(1/Pe)*psi*Theta*diff(U(x, tau),$(x, 2))=-3*psi*xi*(U(x, tau)-Q/K);

 

IBC:={U(x, 0) = 0,U(0, tau) = 1+(1/Pe)*(D[1](U))(0, tau),(D[1](U))(1, tau)=0};

Particle:

PDE:= diff(Q(r, tau), tau) = diff(Q(r, tau), $(r, 2))+(2/r)*diff(Q(r, tau),r);

IBC:={Q(r, 0) = 0,(D[1](Q))(0, tau) = 0,(1/K)*(D[1](Q))(1, tau)=xi*(U-Q(1, tau)/K)};

Pe:=0.01:

psi:=6780:

Theta:=3.0:

xi:=10000:

I will really appreciate your help. Thanks in anticipation.

Hi,

     I'm trying to numerically solve a PDE in Maple for different boundary conditions, however I'm having trouble even getting Maple to numerically solve it for simple boundary conditions.

I have cylindrical coordinates, r, z, theta, and I treat r = r(z, theta) for convenience to plot my solution surface. The initial coundary condition is that at z = epsilon (z = 0 is singular) , r = constant and of course r is periodic in theta. This is just a circle, and the analytical solution is know to be a half-sphere  r = sqrt(R^2 - z^2). I entered my initial boundary conditions into Maple, but it doesn't like the periodic one

IBC := { r(epsilon, theta) = R - epsilon__r,
              r(z, 0) = r(z, 2*Pi) };

pdsolve(
  PDE,
  IBC,
  numeric,
  indepvars = [z, theta],
  time = z,
  range = 0..2*Pi);
Error, (in pdsolve/numeric/par_hyp) Incorrect number of boundary conditions, expected 2, got 1

I'm not sure how to make this work, and then generalize it to more arbitrary intial slices r(epsilon, theta) = f(theta).

Here's the attached worksheet, ForMaplePrimesSUbmission.mw

Any help is appreciated,

Thanks

of a square matrix having its entries 1,2,...16? See http://oeis.org/A085000 for info.

I can;t seem to get DSOLVE working.  Will some kindly soul please send me a complete example, starting with an f(x) & clearly documented?   Many thanks.

 

 

AB

Hello,

On my multibody model, I meet a mistake during the simulation which is the following :

"Constraint projection failure at 10s".

1) Do you have a idea on this error message so as to correct the settings for the simulation?

2) I would like to know more about the projection method. If, I'm not wrong, there is not a lot of documentation about the projection method used in Maplesim. 

   a) Does someone have some references (scientific papers) which present the theory used for the projection method in Maplesim?

   b) In ths sense, I would be very interesting about learning the theory of the projection method in order to be able to tune correctly the following options linked to the projection method :

- Projection Iterations
- Projection Tolerance
- Event Projection
- Event Iterations
- Event Hysteresis

Thanks a lot for your help.

Hello,

In my mechanism, I use absolute coordinates.

For the rotation (namely the initial angles/ angular velocites), I didn't see the difference between Inboard and Euler.

It seems to me that in the two cases, the initial angles are defined with regard to the inertial frame and for both, different kind of rotations can be defined.

Have you some ideas on these two options ?

Thank you for your help.

 

 

PS,
PiFast43 is freely available at,

http://numbers.computation.free.fr/Constants/PiProgram/pifast.html

 

 

 

i dont know what`s wrong with it help me guys

hi,

 

I am trying to implement some data-intensive algorithms like: comuting similarity scores, clustering etc. How efficient Maple is in doing these operations? I mean is it comparable to MATLAB in these operations? What toolboxes are useful in these? I am trying to build a recommender system.

 

I am using Maple18 and not sure if Maple has any advantage in implementing these type of algorithms over MATALB??

 

thanks

siba

Hi all.

I am using Maple2015.

I typed in as input y=x/sqrt(1-x^2).

I hit enter.  The output is:

 y=x/sqrt(1-x^2)

I know the 2 answers are equivalent.

My question is why did Maple swap 1-x^2 to -x^2+1???

Any advice to swap it back would be greatly appreciated.

How to find asymptotic behaviour of a function.

For example at infinity

sinh(x) behaves as 1/2*exp(x)

1/sinh(x)  behaves as 2*exp(-x)

exp(-x)*(exp(-x)+1) behaves as exp(-x)

so that it works with a more complex expression.

First 227 228 229 230 231 232 233 Last Page 229 of 362