Questions on the manipulation of matrices in Mathematica.

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Obtaining the relations of variables using diagonal matrices

I know this is too an elementary question, but I am a pathetic newbie in mathematica and I cannot find any answer by googling. What I want is obtaining some relations of unknown variables using their ...
3
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1answer
77 views

Print array with indices

Is there a single function that prints an array together with the indices? I know how to achieve this with Grid[{Range[n],array},Frame->All], but I vaguely ...
0
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0answers
65 views

Help with calculation of the matrix element( block matrix) of the energy of a quantum dot using Mathematica [on hold]

best regard I am an undergraduate student in physics, and I'm doing my undergraduate work, I am currently studying the electronic structure of quantum dots using the method discussed in the article ...
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0answers
49 views

solving singular matrix [duplicate]

Hello I have a matrix that is singular, and i wanted to use linear solve to solve it but that doesn't work with mathematica. The matrix given as a list looks like this: ...
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0answers
35 views

parsed matrix not deleting elements in adjusted matrix

I have a matrix that has been parsed to delete certain rows and columns, as well as delete certain elements on the diagonal on the matrix. The problem is that it does this in theory when i take the ...
0
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1answer
73 views

Matrix form of complex numbers [closed]

Complex numbers have matrix form. But some 2x2 matrices while differ, represent the same complex number. To compare complex numbers one has to transform the matrices to the form \begin{pmatrix} a ...
2
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1answer
78 views

Design matrix rank does not match

I'm attempting to fit a linear model and Mathematica returns the error message: "The rank of the design matrix 9 is less than the number of terms 10 in the model. The model and results based upon it ...
3
votes
2answers
63 views

How to reflect the entries of a square matrix about its anti-diagonal?

I need help with writing the mathematica code to reflect the entries of a square matrix about its anti-diagonal. I know to do it about the main diagonal using ...
0
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1answer
36 views

Why is there a seeming discrepancy with the expression Cofactor?

I was trying to find out the cofactors of a square matrix. Then I came across the command Cofactor in Combinatorica package. ...
2
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1answer
78 views

Computing with matrix differential operators

I am looking the achieve a working set of Mathematica functions that would allow me to take products, commutators, etc. of (2x2) matrix differential operators and apply them to vector-valued functions ...
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0answers
42 views

How to assign equation solutions to variables [duplicate]

I have 12x12 Matrix with which I have to solve the equation below: ...
3
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2answers
103 views

Help with building matrices

I am a complete beginner in Mathematica and I have a small problem. I have this three matrices (A,B and C) and with them I have to build larger matrix M which looks like this. What would be the ...
1
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0answers
67 views

Fast export of large numerical data

Edit It seems that the bottelneck is not due to eigen value problem. I will esit the question soon. I have a 6000by6000 matrix which I got after some calculations. I want to get the eigenvalues and ...
1
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2answers
65 views

how to get continuation of square matrices with periodic diagonal band automatically?

I want write a function that can automatically analyze any square matrices with periodic band diagonals and give continuations of them. But I can't figure out an elegant way to do this. Suppose we ...
2
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1answer
57 views

Anyone knows the algorithm used by NullSpace function?

NullSpace function gives a list of vectors that forms a basis for the null space of the input matrix. When the rank of the input argument matrix $M_{m\times n}$ is ...
2
votes
3answers
127 views

How to find the kth largest eigenvalue of a matrix, taking into account the sign? [duplicate]

I have a real symmetric matrix m (i.e. its eigenvalues are all real). Eigenvalues[m, {k}] will find the ...
1
vote
2answers
99 views

Get inverse of a matrix step-by-step [duplicate]

How can I get the inverse of a matrix step by step? An example: Given the matrix {{8, 2}, {3, 2}}, the result is {{$\frac{1}{5}$, -$\frac{1}{5}$}, ...
0
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1answer
58 views

How to add an extra column to a current matrix (list)? [duplicate]

a = {{-800, 1712}, {-801, 1713}, {-806, 1832}} TableForm[a] b = a[[All, 2]] - Min[a[[All, 2]]] How do I make a new matrix (list) whic looks like this ...
1
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1answer
66 views

Correlation to Covariance Matrix

I am looking to use the CopulaDistribution fucntion, with a "MultiNormal" kernal. However, for the input, O require a covariance matrix. However, I only have a correlation matrix. Is there a way to ...
1
vote
2answers
54 views

Table operation after export and import of data does not give me the same result

If I create a table of this kind: (m1 = Table[{RandomInteger[], RandomInteger[{1, 5}, {3}]}, {i, 1, 5}]) // MatrixForm which looks like I know how to pick ...
3
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2answers
100 views

Eigenvectors of large symbolic matrix

I have large symbolic matrix of order 32 x 32 given as ...
1
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0answers
93 views

Best way to create symmetric matrices with block structure and additional symmetries of the submatrices

Update: you can now skip the "My attempted solution" part and jump to "My first attempt for improvement" in the end of the question. My question is related to Best way to create symmetric matrices . ...
0
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1answer
58 views

How to use Hold on a variable defined as a graph

I'm working on doing operations on different graphs and getting their probability node degree distributions using a simple algorithm. If I have many defined graphs, for example: ...
2
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2answers
42 views

Findings rows in RREF matrix which contain nothing but a pivot

I am asked to find all rows in a matrix in reduced row echelon form which contain nothing but pivots (pivot is $1$, all other entries are $0$). For example, in this matrix: $$ \begin{bmatrix} 1 ...
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0answers
41 views

Dealing with answers that have Root[ …] when finding an Eigensystem

This is a 3x3 matrix and I think it should solve for the expressions in terms of radicals. I am not sure what to do with this.
-2
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1answer
54 views

Create a matrix by crossing a list

I've a list L of elements. I want to create a matrix by laying each elements of L in both rows and columns where each ...
0
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1answer
52 views

Problem in LinearProgramming [closed]

I wrote a integer Linear programming where matrix c, m and b are: ...
1
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3answers
112 views

Matrices and Combination

When the positive integers 1 to 9, inclusive, are used exactly once as elements of a 3 x 3 matrix, what is the largest possible value of the determinant of the matrix?
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0answers
63 views

Lens profile in a grid

So I have a FDTD code which works and its all good the propagator of the code it self is: ...
0
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1answer
33 views

dropOperator done on Matrix of a Matrix - How is this done?

I have implemented this dropOperator from dropOperator from stackexchange and works fine on a single Matrix. But now I have a Matrix of a Matrix and want to drop some rows or columns (in the pic below ...
0
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1answer
88 views

Block matrix and calculate it's inverse

How to define the following block matrix $$ A=\begin{bmatrix} H-G_1 & -G_1 & \ldots & -G_1 \\ -G_2 & H-G_2 & \ldots & -G_2 \\ \vdots & \ldots & \vdots & \vdots ...
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0answers
84 views

Solving for a Transfer Matrix

I am currently working on a program that will solve a transfer matrix and extract several elements. Particularly, the transfer matrix is characterized by four elements in a ...
1
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1answer
92 views

How to print non zero elements of the matrix containing zero elements and non-zero elements both?

A matrix with both non-zero and zero elements is given. I want to print only the non-zero elements of the matrix. What is syntax that have to be used for this? matr2 = Table[FortranForm[matrixx[[i, ...
2
votes
2answers
77 views

Find the indexes of dependent columns

I have a fairly large singular square matrix, of size 37 and rank 35. Is there a way to get a vector with the (groups of) indexes of the columns in the original matrix that are linearly dependent? ...
1
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2answers
71 views

How to extract matrix which produces given symbolic linear combinations?

Suppose I have a column matrix $\alpha$, consisting of some symbols ...
0
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1answer
47 views

Entering block matrices, general case doesn't work

I want to enter several matrices at different positions in blocks. There is already a very similar answer here: http://mathematica.stackexchange.com/a/3562/6138 I thought that simply generalizing ...
1
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1answer
74 views

What does it mean: “Assuming a matrix | Use a list of lists instead”?

I have entered a matrix by Insert->Table/Matrix->New. After adding it to code, Mathematica wrote a remark: "Assuming a matrix | Use a list of lists instead". ...
1
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2answers
46 views

How to add a part of a list to a function?

I want to be able to add a specific portion of a list to a part of a function but this fucntion intakes 6 variables where as the list is of example: ...
3
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0answers
78 views

Understanding polyharmonic splines

Raul Narain and J.M. gives implementation of the thin plate polyharmonic splines in this post. Raul Narian's method is clear. J.M.'s is convenient to reuse. But J.M. used too many ...
0
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1answer
51 views

LinearSolve in Mathematica, used to find square matrix

Another issue I have with Mathematica today is that I want to solve the following matrix equation: X.b=c where b and c are two vectors, and X is a square ...
1
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1answer
40 views

How to indroduce a value for the functions inside a matrix? [closed]

I would like to assign certain values to the X and Y variables which are inside the functions in the matrix. Thus, I would like to get a matrix with values based on the transformation in Psi matrix. ...
2
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1answer
171 views

Log of a Matrix

I have used the command MatrixLog[m] But it gives natural log of the matrix. How can I find the Log (to the base 2) of a matrix?
2
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1answer
50 views

Sort a vector of vectors of vectors

Let's hope I'm calling it well, I have this vector, or matrix, now I really don't know what it is ...
1
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0answers
49 views

Displaying a matrix as an array of solid rectangular blocks [duplicate]

I would like to plot an array of numbers as a surface, with each number the height of a square, and with the squares connected to adjacent squares with vertical rectangles, up or down as appropriate. ...
-2
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1answer
30 views
1
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1answer
44 views

Easy way to perform multiplication of two 2x2 matrices, that contain list elements?

I have two 2x2 matrices, which elements are lists (so overall structure can be complicated). I need to perform matrix multiplication of these 2x2 matrices as if the elements didn't have its inner ...
2
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1answer
109 views

matrix multiplication speed

Consider the codes below: ...
0
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2answers
43 views

Suggest how to do this matrix multiplication [duplicate]

Have a look at the Mathematica calculation ...
1
vote
1answer
51 views

Insert a linebreak and character repeatedly into a matrix output which is in fortranForm

Suppose I have a very long string which is a11 element of matrix a11=2*gopsv-2*Bgopsvw+2*acgmops*v+2*cgmopsv*B-2*acgmopsvB+3*gmopsvB-3*BgmopsvwB+m*w2*B +5*acgm2 +opsvB -ac*m2*w2*B +cgm2*opsvB* - ...