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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

Simplify matrix...

August 28 2014 Leon 0

Dear all,

 

I've a very complicated matrix, and I'm unable to read the result by maple. It should be a 6x6 matrix.

What mean the following expression ?

Thank you for your help.

 

 

 

Hi Again

Assume that we have known matrix namely, Q, of order (m+1)*(m+1) and we want to construct following matrix

where 0(bar) is zero matrix of orde (m+1)*(m+1) and New matrix should be of order {N*(m+1)}*{N*(m+1)} where N is known constant.

thanks for any guide


Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

Hi all.

Assume that a Matrix P is (m+1)*(m+1) known matrix and we want to construct following special matrix

where

and

how can we do it by maple?

Note that the required matrix is of order k(m+1)*K(m+1)

 

thanks for any guide

 

Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

I am trying to find a way to take the rows of a matrix and put them in a sequence.  For example if i have the matrix 

M:=Matrix(3,[[1,1,1],[2,2,2],[3,3,3]]);

I want to rewrite it as S:= {111222333}.  

Sorry if this is not clear.  I know how to create a sequence, but I want to be able to use the Matrix and output a sequence without manually inputing the numbers.  

Thank you in advance for your help.  

I am finding it a struggle to do this trivial task in Maple.

Given a matrix, I simply wanted to find the positions (index i,j) of all elements that meets some condition. For example, given matrix A:=[[1,2,3,],[4,5,-1]]; I want to find the index of all elements >=3, so the result should be a list of set such as

         [[1,3],[2,1],[2,2]] 

I tried to use member with 'pos' option but that does not work for matirx. It seems only designed for 1D

A:=Matrix( [ [1,2,3],[4,5,-1]] );
c:=select[flatten](x->x>=3,A);  #tried without flatten also
member(c,A,'pos');
pos;

Then I tried rtable_scanblock(), which is the most convoluted and badly documented command I have ever seen in my life (for such a complex command, one will expect 100 examples of many sorts of functionality to illustrate how to use, but only 3-4 trivial examples exist and 3 of them pretty much the same).  What is operation_passindex? what is operation_passnoindex? how to use them? Why is there a star next to val* and operation* ? What is passindex actually? is it a name? value? proc?  etc.. Worst help page ever. 11 parameters for a command??

This is what I tried:

A:=Matrix( [ [1,2,3],[4,5,-1]] ):
rtable_scanblock(A,[],(val,ind,res)->( evalb(val>=3),[ind,val],res),[[1,1],A[1,1]]);

So the result I want is there. I just do not understand why the true,false and those last entries are there and how to get rid of them. I tried. I think I need one other options, but I am lost with all the options listed there with no examples on how to use them.

rtable_scanblock(A,[],(val,ind,res)->`if`( val>=3,[ind,val],res),[[1,1],A[1,1]]);

but then I get only the last value:

I tried

rtable_scanblock(A,[],(val,ind,res)->`if`( evalb(val>=3),[ind,val],res),[[1,1],A[1,1]]);

no difference.  I think I am close, but after 30 minutes, I am calling it quit. If something so easy takes that much effort to find how to in Maple, then something is wrong.

In Matlab, I do this with my eyes closed:

A=[1,2,3;4,5,-1];
[I,J]=find(A>=3)

I =
     2
     2
     1
J =
     1
     2
     3

In Mathematica, such as trivial

mat = {{1, 2, 3}, {4, 5, -1}};
Position[mat, x_ /; x >= 3]

                 {{1, 3}, {2, 1}, {2, 2}}

Thank you

 

Hi all.

Assume that we have:

Where Q is known matrix. how can we produce this vector by maple?

Thanks a lot
Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

Hello,

 

in summary, I have a problem with the evaluation of a matrix multiplication between matrices with trigonometric entries.

Im a bloody beginner with Maple, so sorry in case this question is stupid or I posted in a wrong way!

 

There is the 6x6-Matrix  L, which has entries like:  Lmn = L1 + L2 cos(2 phi + phi_0).

I want to transform this Matrix L with  the 3x6 rotational Matrices T and its 6x3 Inverse-Matrix  T_p_inverse, 

like:                              L_transformated = T * L * T_p_inverse

 

The problem is, that I don't get Maple to simplify the solution.

I tried combine, simplify, expand, evala, but maple does not combine and simplify the solution. Due to the trigonometric entries and orthonomal row-vectors in T, I expect the solution to be quite simple.

Attached you find my worksheet!   transformation_L.mw

It would be great if somebody can help me or give me a hint!

Thanks a lot!

nilssson

 ---------------------------------------------------------------------

Here are the exact Matrices:

 

 

 

 

 

I figured how to insert row in middle of a matrix using <<>> notation. But I am trying to stick to one notation which is the Matrix() and Vector() for now. 

Here is what I am trying to do. Insert a row in the third row of  Matrix. This works:

A:=< <1|2|3>,<4|5|6>,<7|8|9>>;
A:=<<A[1..2,..],<90|91|92>,A[3,..]>>;

But when I try

A:=Matrix([ [1,2,3],[4,5,6],[7,8,9]]);
A:=Matrix([ A[1..2,..], [91,92,92], A[3,..] ]);

Error, (in Matrix) this entry is too tall or too short: [91, 92, 92]

I also tried:
A:=Matrix([ A[1..2,..], Vector[row](91,92,92), A[3,..] ]);
A:=Matrix([ A[1..2,..],Matrix([[91,92,92]]), A[3,..] ]);

I am starting to think I should go back to using <<|,|,|>> notation, even thought I do not like it, but at least it seems more logical. 
How would you insert row in middle of matrix, using Matrix() constructor from an existing Matrix?

 

 

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