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I really need help!
please help to solve the boundary value problem by method of shooting.
I never met with this problem and I can not quite figure out how to solve this problem in maple
Thanks for the help!

 the problem


This post is an index page for reading the Parallel Programming blog posts.

Hello, everyone. I have some problem with multithreaded calculation. I just need calculate eigenvalues of matrix m at various parameters (and then export to a file) using advantages of the parallelizing. The following code works but in serial way

 

restart: with(LinearAlgebra):

m:=ImportMatrix(cat(currentdir(),"m.txt")): # here is matrix m.txt

step:=1:

 

prc:=proc(k1,k2)

local u,i,j,nmc:

u:=Matrix(ceil(1+(k2-k1)/step),5):

u[1,1]:=k1:

for i from 2 to op([1,1],u) do

u[i,1]:=u[i-1,1]+step:

end do:

for i from 1 to op([1,1],u) do

nmc:=sort(Eigenvalues(m*u[i,1], output='list')):

for j from 2 to op([1,2],u) do

u[i,j]:=nmc[j-1]:

end do:

writedata[APPEND](cat(currentdir(),"u_",convert(k2,string),".txt"), [convert(Re(u[i]),list)]):

print(u[i,1]);

end do:

return finished:

end proc:

 

with(Threads[Task]):

Start(ArrayTools[Concatenate], 2, Task=[prc,1,20], Task=[prc,20+step,40]);

quit:

 

The Start(ArrayTools[Concatenate], 2, Task=[prc,1,20], Task=[prc,20+step,40]) function makes two tasks of calculation at the parameter ranges of 1-20 and 21-40. But in this case Start spends twice more time than simply prc(20+step,40). How to realize a multithreaded calculation?

By the way I don't need to use a Concatenate function in Start but without any procedure Start doesn't work.

I have a statistics task that is very complicated to me, and I would really appretiate some help!

I believe that I have completed task a, but task b and c seems to be too hard for me to grasp.

Here is a presentation of the task text:

 

xi 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
yi 12.3 12.8 16.8 17.9 20.5 22.7 24.9 27.5 26.9 29.4 30.3 34.2 36.4 36.7 41.1

Assume that the data represents independent realizations of a "linearlnormal" model.

Yi = α + β xi + ei i = 1..15,

where ei˜N(0,σ), where sigma is unknown.

 

(a) create a scatterplot of the data {f(xi,yi)}15 ; i=1
Then calculate the empiric correlation coefficient.

(b) Find the minimum least square estimate for α & β.

(c) Create a 95% confidence interval for the parameter β. What does this confidence interval express?

Is there anyone out there who are able to help me with some maplecode?


thanks in advance,

Soeta

This blog post is a response to a post on MaplePrimes.  MaplePrimes user wkehowski asked how the Task Model could be used to filter combinations.  The basic problem is formalated like this:  We want a function, I'll call it FilterComb, that accepts positive integers...

In the following task procedure, when i>1, it works well,but if i=1, the task(M,1,5) returns error

restart

I am planning to use the "schedual task" in windows to try to launch
maple in the background (run under some different user account)
to do some computations.

For this pupose I have designed a little counter that is located in the
Start up code region:

for i from 0 to 100 do
if DataTable1(1, 1)=i then DataTable1(1,1):=i+1:  break; end if:
end do:

the DataTale will tell me how many times the worksheet has been opened
just to check...

Is there a way to plot a function in a multithreaded way?

I have a computing-intensive function (eg. integral over Hermitian-Polynoms), which I want to plot. I couldn't find a way to do this such, that all my cpu-cores are used.

Any suggestions?

Thanks!

Hello, MaplePrimes!

I want to create a custom component to model dynamics of a movable pulley, which can rotate and move along some direction (translational motion). I’ve got dynamic system, which describes both motions of a pulley. Some information about this dynamic system:

 

I want to download historical data from google finance for two Indecies simultaneous
but I dont understand where the output is saved...?!  Also should I use task or threads ?


restart:
with(Sockets):
with(Threads):


X1 := proc () local str, sid; global b; str := "";

sid := Open("google.com", 80);
Write(sid, cat("GET /finance/historical?q=INDEXSP:.INX&histperiod=daily HTTP/1.0 \n\n"));

b := Read(sid); while b <> false do str := cat(str, b...

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