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I have written a code that computes the fourier-bessel series of a function over the period [a,b].
When I wanted to get some numerical results, I noticed that it takes lots of time for maple to numerically compute the coefficients of the series. Each coefficient of the series is expressed in terms of some integrals that I was expecting maple to compute them in few seconds, however, when  I want to compute "N=100" terms of the series, it takes lots of time.

I was wondering if there is any way to boost up the numerical computation time. I will appreciate any help.

Below you can find my code.

Example_2.mw

Many many thanks for your attentions! :)

Say I have

a.mpl

b.mpl

c.mpl

each of them can be ran seperately. While I am running a single file, it looks like that the machine is not "using" too much computation power. I wonder if it's possible to run multiple at the same time ?

My CPU is i7 940X, with 4 dual core processors, so it has 8 threads.

I know that the GUI can run multiple worksheets seperately, but if in one of the worksheet, i click "run all" (!!! botton),  I will have to run each line separtely by clicking one at a time.

Is there a better way to do this? What's the best way to do this? I hope to somehow 'maximize' the full use of my CPU (without changing the code).

 

casper

Hello.

Two related questions: I'd like to measure the CPU time used by a computation. Should I use with(CodeTools)? or use  time[real]? What would be the most accurate way to measure the CPU time used by one call, say dsolve()?

Also, How would one return both the result of the computation and the time used in one call so that one does not have to make two separate calls: to obtain the result and to obtain the CPU time?

Example:

restart;
with(CodeTools):
ode:=2*a*x^3*y(x)^3+2*x*y(x)+diff(y(x), x);
result:=Usage(dsolve(ode=0,y(x)),output='cputime');

Gives result:=0.141 while

restart;
ode:=2*a*x^3*y(x)^3+2*x*y(x)+diff(y(x), x);
result:=time[real](dsolve(ode=0,y(x)));

Gives result:= 0.145

But in both cases, I have to make another call to get the result of the DSolve in this example. result:=dsolve(ode=0,y(x)); which I'd like to avoid if possible. 

I am using Maple 18

 

I have a rank 1 array M of 1000 values.

I want to apply a function f on each value of M and its location giving,

[f(1,M[1]), f(2,M[2]), ... , f(1000,M[1000])]

is it possible to get this using map or map2 or map[n] or maptype (without using seq since its slowing down computation).

inotherwords can i access the member location inside a map evaluation?

Slides of the presentation at the VII Workshop Fast Computational and Applied Mathematics developed in graduate school at the National University of Trujillo. January 8, 2014.

 

Visualización_Geomét.pdf

 

L. Araujo C.

I work entitled Point Exeter made ​​for Fast VII workshop on applied and computational mathematics 2014 Trujillo Peru.

  Punto_de_Exeter.mw   (version in spanish)

Atte.

Lenin Araujo Castillo

Physics Pure

Computer Science

 

Thanks to the community through Maplesoft Mapleprimes that could develop in Computational Mathematics Achievement Day at our institution.

Two questions:

The algortihms that Groebner[Basis] uses at each step computes some "tentative" or "pseudo-basis". The "tentative" basis is not a Groebner basis but it is in the ideal generated by the original system of polynomial eq.

1) Is this correct ? Provided this is correct, then

2) How can one retrive the last "tentative" basis?
 If I just use timelimit I can abort the computations but how can one retrive the last computation?

 

I am to program a computation on maple.
But I get the message :

Error, unable to match delimiters

followed by the full sequence of command.

 

How can I do to fix this problem?

As described on the help page ?updates,Maple17,Performance, Maple 17 uses a new data structure for polynomials with integer coefficients. Our goal was to improve the performance and parallel speedup of polynomial algorithms that underpin much of the system and create a platform for large scale polynomial computations. Shown below is the new representation for 9xy3z

The operation: 2^29.403243784 gives me 7.0999999820*10^8.

However, using WolframAlpha, the answer is 7.10000000139658667836958142950829925944726171959 × 10^8.

These are 2 different answers. Can someone offer an explanation as to why this occurs and how I can avoid this problem?

Thanks in Advance!

Eddy Liu

I was working with the computation of the eigenvectors of a 3X3 symmetric matrix with algebraic entries and Maple 17 doesn´t give me an answer after a long time, even with CUDA activated. You can see this by the commands below:

 


Dear Sirs,

I am a post-doc working on the university and I am dealing with elliptic integrals together with Maple, nowadays. I am using for my computations en EllipticK(.) function and I need to know how this function computes its exact values for a given parametr of an elliptic modulus. Does it use some kind of a series(how does it pertinently look like?) or is it tabelated and consequently interpolated? Please, will you be so kind and could you give...

The MRB constant can be computed in Maple by evalf(sum((-1)^n*(n^(1/n)-1),n=1..infinity)).

On my laptop restart; st := time(); evalf(sum((-1)^n*(n^(1/n)-1), n = 1 .. infinity), 500); time()-st gives a timming of 37.908 seconds.

Using the procedure posted at the bottom of this message st := time(); A037077(500); time()-st gives a much faster timing of 1.903 seconds.

My fastest timing for 500 digits of MRB comes from my...

Hello Maple wizards,

I have two questions for you today.

First, a program I'm developing in Maple 15 does frequent matrix multiplication with a constant float[8] matrix. I hope to take advantage of multiple processors in my 6-way desktop processor and/or CUDA features of the Nvidia GPU card. The program is large enough that maintainability and good programming practice dictate that it be broken down into multiple procs. In addition, I'm considering...

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