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I need create a matrix with 3 dimensions, but I don't know how can I do this. The variable that I need store could be write in this form:


>S[i,j,k];

I don't want write this with subscript but like a matrix. 

Hi,

i need to remove all the elements from a matrix that are almost zero, for example, from this matrix:

matrix = (Matrix(2, 2, {(1, 1) = 1/1000000000000000000, (1, 2) = 1, (2, 1) = 1, (2, 2) = 1}))

i need to remove the smallest element, so the final matrix will be like:

matrix = (Matrix(2, 2, {(1, 1) = 0, (1, 2) = 1, (2, 1) = 1, (2, 2) = 1}))

Is there a simple way to do that? Maybe forcing Maple to use number above a threshold?

 

Thanks

 

I have a set "EQ" containing N linear equations in N unknowns. The only symbolic variables in each "EQ[i]" are the unknowns. I want to write a procedure that derives the matrices "A" and "b" where A.x=b is the same linear system stored in "EQ". In other words, I want to write the linear system in the matrix form.

Can anyone guide me through writting such a procedure?
As an example do it with the system written in the following file.

Note: This procedure will be used for large linear systems (e.g. 2000 Equations, 2000 Unknowns) so it will be important that the procedure uses the least operations required.

LinearSystem.mw

Thanks in advance.

Hi there,

I was trying to simulate the behaviour of a one-variable, discrete-time function having three parameters.

The function reads

M[n+1]=(b·theta^(m)·R[n])/(theta^(m)+R[n]^m)

defined for b, theta, m > 0

Say I want to simulate the function for the following values

b := [seq(1 .. 10, 1)];
theta := [seq(1 .. 5, 1)];
m := [seq(1 .. 2, 1)];

for n from 1 to 10.

 

I guess I need to build a 4-dimension array. But I was not able to find the right way to do this: should I use the Array strucutre? and if yes, how would I do it? As far as I've read, indexing would be an issue: should I create special indexing functions?

If I'm not wrong Maple matrices (Matrix) are just 2D.

 

Once the values of M computed, I would like to generate the corresponding plots, varying one parameter while the other two are fixed, and drawing the different M's in the same plot.

How can I achieve this?

Furthermore, if I would like to generate all possible combinations, I guess I would need to insert the solution given to the above question within a for loop. Will Maple display all plots or will it overlap/overwrite the preceding plot if used within a loop?

 

Thanks,

jon

Hi

How can I substitute a function in a matrix? This is what I tried but it's not working at all:

lign1:=x-y+2*z=1:
lign2:=(-2)*x+y+z=0:
lign3:=(-4)*x+y+7*z=2:
lign4:=3*x-2*y+z=1:
T := GenerateMatrix([lign1, lign2, lign3, lign4],[x, y, z], augmented);

Then I'd like to substitute another function with lign1:

lign5:=x+y+z=6:
T2:=subs(lign1=lign5, T);

But T2 = T and that wasn't really the point.

 

Sorry if the answer is obvious no amount of searching has helped me so far. I hope this question isn't too ridiculous.

Thanks

Hello,

first of all, this is my very fist question in this forum, so please excuse some formal mistakes I may make...

Using Maple 18.01 on Windows 7 64bit

To the topic: I want to calculate the eigenvalues of a complex matrix like this (just as an example):

M := Matrix(2, 2, {(1, 1) = a+2.5*I, (1, 2) = 1-I*a, (2, 1) = 4, (2, 2) = a})

When I try to calculate

Eigenvalues(M)

I get

Error, (in LinearAlgebra:-Eigenvalues) expecting either Matrices of rationals, rational functions, radical functions, algebraic numbers, or algebraic functions, or Matrices of complex(numeric) values

Strange, because if I replace the "2.5" with just "2", so an integer instead of a float, I get results:

I don't understand this strange behavior, since Mathematica i.e. calculates everything just fine...:

Thanks in advance for any suggestions.

solve([b+c = a*a1+b*a4+c*a7, a+c=a a2+b a5+c a8, a+b = a*a3+b*a6+c*a9], [a1,a2,a3,a4,a5,a6,a7,a8,a9]);

how to assume a1 to a9 are 0 or 1

and find one of possible matrix is

Expected Result := Matrix([[1,1,0],[1,0,1],[0,1,1]]);

Hi all

How can I construct following triangular block matrix?

where

and

P is (N*M)*(N*M) and E and H are M*M matrices. tf is known constant.

thanks in advance

 

Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

Hi all,

Assume that we have a vector, namely v:=[1,-2,3,-4] and we want to construct special matrix namely Z, from Vector v as follow:

first row is 1, secnond row is -2,..., the end row is -4 namely
Matrix([[1,1,1,1],[-2,-2,-2,-2],[3,3,3,3],[-4,-4,-4,-4]]);

in the other word every row of matrix is 4 times corresponding componet in vector.(for example v is (1*4))

how can we do this?

best wishes

Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

Hi,

 

I am trying to find the inverse of 8x8 generic symbolic matrix. Everytime I evaluate the program I get the following error:

 

Error, (in expand/bigprod) Maple was unable to allocate enough memory to complete this computation. Please see ?alloc

 

Can anyone guide me how to increase the memory allocation? And would that solve the problem for me?

 

Any help is appreciated.

 

Thanks!!

Hi,

How are you. Nice to meet you once again.

I need your help  to give an answer to  this question:

I have two vector v1:=[1,2,3,4,5,6,7,8]; and v2=[9,10,11,12,13,14,15,16];

I would like to construct a matrix whone first colunm is v1 and last colunm is v2 and all the rest is ZERO.

Many thinks.

 

 

 

I'm working on a complex problem in Composite Materials. I've gotten to a near-result 6x6 matrix, with several cells containing polynomial denominators. I have an equation for simplifying these, which boils the polynomials down to a single variable, but I can't seem to get it to substitute in. Can anyone help me solve this? The problem is also time-sensitive.

 

Hi there

I've got an 18*18 matrix which almost all of its elements are in parametric form. I Need to export this matrix to MATLAB to do some numerical alnalysis on that But when I click on  " export as MATLAB", the following error appears:

"can not convert matrix elements to float[8] datatype"

I wonder if thre's a solution to that or anyother way to move the matrix(as it is) to MATLAB.

I'll be appreciated your help

I'm used to Mathcad, and I am very new to Maple. Something I cannot figure out right now is how to define multiple elments of a matrix using a function.


Input Data

Define system dimensions as n:=2;

i:=1..n;

j:=1..n;

lambda:=Matrix(n);

Lambda:=Matrix(n);

upsilon:=vector(n); 

Minor side note: I originaly had upsilon defined using the syntax "Vector[row](ncomp)", but this was giving me an 'exponentiation' operation error, so I changed it to what it is now (basically a list/array, which I guess has different type definitions that no longer cause the error?).

lambda[1,2]:=471.0433;

lambda[2,1]:=883.7530;

upsilon[1]:=58.69;

upsilon[2]:=18.07;

The Problem I'm Having

Now I just want to define Lambda using a function to define all elements (like I would in Mathcad).

Lambda[i,j]:= (upsilon[j]/upsilon[i]) * exp (-lambda[i,j]/2853);

which gives me an extremely long error message:

Error, invalid input: exp expects its 1st argument, x, to be of type algebraic, but received Matrix(2, 2, {(1, 1) = -0.3504976272e-3, (1, 2) = -.16509955895845776, (2, 1) = -.30975332953088164, (2, 2) = -0.3504976272e-3}, datatype = float[8]

As far as I can tell (keep in mind that this is my very first Maple project) that it doesn't like lambda as a matrix? But shouldn't it just evaluate to the element? and why is (2,2) and (1,1) giving values, because it should intialize to zero, so exp(0) = 1 in these cases??

I tried to simplify further by just trying

Lambda[i,j]:=(upsilon[j]/upsilon[i]);

but then it just gives me 1, and when I look into Lambda all the elements are now 1 when only the diagnol elements should be 1 (the rest some fractional amount)??

I am at a complete loss. I thought about doing something like For i = 1 to n etc. but then it just looks like coding, which defeats the purpose of trying to make a calculation sheet documenting the procedure...

Any help and/or insights into what I am doing wrong here would be most welcomed :)

P.S. I've just noticed that there is an upload option :/ Wilson_Equation.mw.

 

Hi all

How can I produce following matrix by maple?

the order of matrix should be {N*(m+1)}*{N*(m+1)} where N is known constant

 

thanks for any guide

 

Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

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