I'm writing some code that computes a positive integer N and I'd like Maple to define a function of N variables. I've tried writing 

f := (seq(t[i],i=1..N))-> MY EXPRESSION;

but I receive the error

Error, invalid parameter; functional operators require their parameters to be of type symbol or (symbol::type)

Is there anything I can do here?

123.mw

i make two component that the left named MathContainer0 and right named MathContainer1

which can enter any numers on it

and i want to solve the eqution such as  

x*%MathContainer0+y*%MathContainer1=0 ,and y*%MathContainer0+x*%MathContainer1=0

but it still not shows the answers i want

anyone can help thx

hi 

what is problem ?

Download u(x_y).mw

How to create a long progression in maple (up to 100 000 000 000), where a member is a previous one plus a certain number. For example: 25, 50, 75, 100... and then divide the whole series (all the members) by a number. What command should one use?

Hi all,

I try  to plot phase portrait the below DAEs, 

diff(S(t), t)=-β*(1+δ*sin2Πt)*S(t)*I(t)-μ*S(t)+μ,

diff(I(t), t)=β*(1+δ*sin2Πt)*S(t)*I(t)-γ*I(t)-μ*I(t),

0=S(t)+I(t)+R(t)-1.

where

μ=0.01,

β=1510,

δ=0.02,

γ=50,

I really appreciate your help.

a:=rand(0..8):
b:=rand(0..8):
c:=rand(0..8):
d:=rand(0..8):
e:=rand(0..8):
f:=rand(0..8):
a()+b()+c()+d()+e()+f()=8;

This is my  programming code.

I want ot set six random summation is  8. 

But the random summation can't reach 8.

Hi, 

  I would like to a string of characters to a file. For example,

***

str:="hello world";
WriteFile[APPEND]("D:\\output3.txt", str);

***

  It doesn't work. I did not get output3.txt :(  How should I do, to write a string of characters, such as "hello world" to a file?

Thank you

qu.mw 

this is my code but there has smoe problom

i make the MathContainer0 and MathContainer1 can be entered number

 i plot the loop circle, and then i want to show te insection of two circle,that the center and radius of two 

 depends on the value of MathContainer0 and MathContainer1 that we entered

any one can help me? thx

Good morning.

I am working on engineering drawing project. I request your kind suggestions for

the above cited subject.

With thanks & Regards

M.Anand

Assistant Professor in Mathematics

SR International Institute of Technology,

Hyderabad, Andhra Pradesh, INDIA.

Dear all,

I tried to use pdsolve to solve the parabolic pde but get the unexpected answer:

Is it the PDESolStruc or the other structure? Where can I find the description about this kind of structure.

Thanks.

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

Hi,

  I have a loop code, such as

****

i_max:=10;

for i from 1 to i_max do
  blah blah blah

end do;

****

  I would like to clean memory, something like restart suppose to do, after each cycle. Restart could only work at top level. How should I do to clean memory after each cycle?

Dear all,

I want to compute the charateristic polynomials of some matrices (the number of matrices is more than 10000), and write the coefficients of the resulting polynomials to a text file. The entries of the given matrices are stored in a text file. More specifically, suppose that M_1, M_2 and M_3 are three matrices, and the entries of them are stored in a text file named "data.txt" in the following form:

1 2 3

4 5 6

7 8 9

1 -1 0

2 3 6

-3 0 2

2 1 -1

1 -1 -2

0 1 2

The resulting output file should be of the following format:

1, -15, 18, 0

1, -6, 13, -28

1, -3, 1, 3

I don't know how to repeatedly read the data from the given text file. I think the procedure should be as follows.

>restart:

>with(LinearAlgebra):

>with(FileTools:-Text):

>fid:=Open("data.txt"):

>fid_1:=Open("data_1.txt"): #data_1 is the output file

>ReadFile(fid); #since the number of matrices is very large, I want the data to be read once

>numlines:=CountLines(fid);

>for i from 1 to numlines do

       here I need repeatedly read the data to a matrix M (I don't know how to do);

       P:=CharacteristicPolynomial(M,x);

       writedata[APPEND]("data_1.txt",map(i-> coeff(p, x, i), [seq(i, i = 0 .. degree(p, x))]));  #this statement cannot write the coefficients of a polynomial in the same row

>end do;

>Close(fid):

>Close(fid_1):

Now as I'm pretty new to Maple, I don't know any better and can't seem to get any information out of the help documents. 

Thanks a lot.

Hi,

So I wrote this script (30 lines) in Maple and it works fine. But now I want Maple to repeat the script while changing my input variable.

My variable is T and I want Maple to perform the script for T=0 to T=15 and with a step size of 0.1.

I tried for loop and proc, but could not make it work. What is the most appropriate way do this?

Thank you.

Hi everyone. Could I work with functions of complex variable in maple ?