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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...

I'm thinking about getting a new laptop (since the current one is kind of outdated). I use a lot of Matlab, Maple and Mathematica and will be doing come cfd computations. I found two laptops which, for the same price, only differ in processor and screen size. One features a i7-2620M and has a 13' screen and the other a i7-2670QM with a 15' screen. What I need to know is if the difference between processors is significant enough for me to turn a blind eye on portability ...

When using the command "for", the results are placed in a column,such as if we input
for i from 1 to 3 do  i end do, the results are showed as

1

2

3.

This style is not convient to use for following computation. So how to put all results into a list or set ?

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