Linked Questions

1
vote
2answers
2k views

Symbolic determinant is not computing [duplicate]

I'm trying to compute the determinant of a symbolic matrix made with the following code: ...
0
votes
1answer
2k views

Display problem multiplying matrix [duplicate]

I'm multiplying matrices and I don't get answer I want I just get matrix M times matrix N, there is no result. What to do and ...
2
votes
1answer
614 views

Mathematica won't multiply a numeric matrix by a symbolic matrix [duplicate]

If I1 = {{1,0},{1,-1}} and Acl = {{A , -B*K},{C*L, A-B*K-C*L}} where A, B, C, and D are not defined in the notebook. ...
1
vote
1answer
319 views

why does matrix multiplication in mathematica not produce one single product matrix [duplicate]

How can I get one single product matrix? Please help! Now:
0
votes
2answers
84 views

How to calculate $(X^tX)^{-1}X^tY$? [duplicate]

This is MatrixForm[ {{1., 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, {1, 1.5, 1.5, 1.5, 2, 2, 2.2, 2.4, 2.5, 2.5, 2.8, 2.8, 3, 3, 3.2, 3.3}}] $X^t$ ...
0
votes
1answer
404 views

How can I force Mathematica to take the dot product here? [duplicate]

The code: vec1 = {{-1}, {0}, {1}} // MatrixForm vec2 = {{-1}, {1}, {0}} // MatrixForm p[v2_, v1_] := v1 (v1.v2)/Sqrt[(v1.v1) (v2.v2)]; u2 = vec2 - p[vec2, vec1] ...
2
votes
1answer
113 views

Unexpected behavior from `NumberForm` of a matix [duplicate]

If I calculate the dimension of the matrix after NumberForm directly, then there will be something wrong ...
1
vote
0answers
295 views

Matrix multiplication involving MatrixForm [duplicate]

Possible Duplicate: Why does MatrixForm affect calculations? I am doing a matrix multiplication, but not getting the desired output. I am doing the matrix multiplication of $A^{-1}B$ from the ...
0
votes
0answers
261 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: ...
0
votes
2answers
91 views

Suggest how to do this matrix multiplication [duplicate]

Have a look at the Mathematica calculation ...
0
votes
1answer
140 views

Problem with List Dimension Outer Map [duplicate]

I am currently handling a big list which has the following dimension: {6, 3, 4, 2, 2, 1, 8} where the last number 8 represent a ...
0
votes
1answer
129 views

Why does Eigenvalues[matrix I defined] not work? [duplicate]

This is the code I have in my mathematica notebook. I want to find the eigenvalues of the matrix I created called Hmatrix as defined below. However when I type Eigenvalues[Hmatrix] I get the Hmatrix ...
1
vote
1answer
105 views

How to interchange columns of a matrix? [duplicate]

Suppose I have a matrix M={{1,2,3},{4,5,6},{7,8,9}}//MatrixForm What code do I write to interchange columns and make it into ...
2
votes
1answer
61 views

The ArrayFlatten seems to have no effect for some reason [duplicate]

I am a new Mathematica user, I am attempting to use ArrayFlatten but it seems not to work in this case. My codes are below, ...
2
votes
1answer
60 views

Unexpected behavior of ScientificForm when applied to a list [duplicate]

Consider a = Table[1, 100] la = Length[a] b = ScientificForm[a] lb = Length[b] la = 100 and ...
0
votes
0answers
68 views

'MatrixForm' problem [duplicate]

I prefer to use 'MatrixForm' because the form looks better in matrix manipulation. But my current problem is that after the use of 'MatrixForm', subsequent matrix calculations like 'Det' or 'Inverse' ...
0
votes
0answers
68 views

Inverting a matrix [duplicate]

Possible Duplicate: Why does MatrixForm affect calculations? I am facing a strange behaviour from Mathematica when asking it to invert the following matrix: ...
0
votes
0answers
51 views

How do i transform a Matrix into a List? [duplicate]

Like the title says i want to transform a Matrix into a list so i can use LinearSolve what's the way to do it? ...
0
votes
0answers
49 views

Difference between matrix rapresentation [duplicate]

I've noticed different behaviour in Mathematica between matrix representation: The matrix a={{1,2},{3,4}} is different from b=a // MatrixForm Why i obtain ...
0
votes
0answers
41 views

Why isn't the matrix product computed? [duplicate]

Possible Duplicate: Why does MatrixForm affect calculations? I have the following input: http://wstaw.org/m/2012/11/15/geogebra4.png Why is the matrix not computed, giving me a $2 \times 2$ ...
0
votes
0answers
41 views

Why doesn't this evaluate further [duplicate]

The figure above shows the code as typed into Mathematica. In the fourth last line (or In[15] as you prefer) the expression is not evaluated to the fullest extent possible. Why does this occur? I ...
0
votes
0answers
39 views

Mathematica wrongly displays rows instead of columns [duplicate]

I want to perform some operations with certain column but when I tried to display the first column as it is shown in attached picture 1 (in some reference on web) of the table but Mathematica ...
0
votes
0answers
37 views

Matrix Vector multiplication [duplicate]

I have a rather simple question which surprisingly i could find the answer theres a matrix $U $ whith is $4*4$ and a vector $A$ which is $4*1$ and when I wand to multiply them by $U.A$ operator i get ...
0
votes
0answers
32 views

Adding two matrices together results in a weird result [duplicate]

I want to add two 10 by 10 matrices (same dimension) together but get a weird result. This is the screenshot of it: The matrices are defined in this manner: ...
0
votes
0answers
27 views

Using functions as input for a function - won't simplify [duplicate]

I've defined a function P[k_] := 1/[Sqrt]2 (R[k] + L[k]) where R and L generate matrices. However the output of this function never full simplifies (even when I use the Simplify[%] functions). It ...
0
votes
0answers
25 views

Matrices multiplification [duplicate]

I have to multiplty 2 matrices in Mathematica, but I have no idea how to force simplification. I create matrices by A={{a,1,b,},... and multiply using C=Dot=[A,B]//MatrixForm My problem is that ...
0
votes
0answers
20 views

Why do I have to index my covariance matrix as if it has 3 dimensions [duplicate]

The language reference for getting parts of a matrix seems to make sense. I'm wondering why my covariance matrix behaves differently. ...
0
votes
0answers
20 views

Using Eigensystem to solve eigenvalue problem [duplicate]

I'm trying to solve an eigenvalue problem of the form: $\textbf{A}\vec{x}=\lambda \textbf{B}\vec{x}$, where A and B are square matrices, $\lambda$ are the eigenvalues and $\vec{x}$ the eigenfunctions. ...
1
vote
0answers
19 views

Problem subtracting matrices [duplicate]

I am trying to study eigenvalues and eigenvectors using Mathematica. I am trying to compute $A-\lambda I$, so I created a matrix A and a matrix with $\lambda$ in the diagonal: ...
0
votes
0answers
18 views

Matrix multiplication Q.W not working - Result=matrix Q . matrix W [duplicate]

When I write the code to do the dot product between two matrices, Mathematica does not compute it: How can I get the right matrix? EDIT Thank you for your willingness.
0
votes
0answers
14 views

Rank of symbolic matrix [duplicate]

I can't figure out why Mathematica can't calculate rank of a symbolic matrix. Please take a look at the attached screenshot below. If you need the full source code then you can find it in the "...
0
votes
0answers
11 views

Creating 3x3 Matrix using Table Function and then accessing an element [duplicate]

I use the table function to create a 3x3 matrix in index notation. I assume that I can access the element in first row and first column using A[[1,1]] but instead ...
13
votes
4answers
1k views

How to solve this matrix equation

How to solve this matrix equation Solve[MatrixRank[( { {1, x, 3}, {2, 4, 5}, {2, 4, x} } )] == 2, x, Reals]
14
votes
3answers
354 views

Head of a MatrixForm expression?

An example in http://www-zeuthen.desy.de/theory/capp2005/Course/hahn/mathematica.pdf amounts to the following ...
5
votes
2answers
5k views

How to make Mathematica show matrices and vectors nicely

It shows me like {{0}, {1}, {0}, {-1}} . Is it possible to make it look like a vector, always?
4
votes
2answers
3k views

How to compute the partial trace of a 4x4 matrix?

I want to compute a partial trace using formula $\rho_A=\sum\langle B|\rho_{AB}|B\rangle$ . Example, $\rho_{AB}= $$ \begin{pmatrix} a & b & c & d\\ e & f & g & h\\ i &...
5
votes
1answer
3k views

How can you convert a matrix back into a list of lists?

It is very simple in Mathematica to convert a list of lists into a matrix: all you need to do is apply the //MatrixForm function to it and voila. Is it possible ...
4
votes
3answers
432 views

Generating all 2x2 matrices with entries from 0 to 3 whose det is 1 with mod 2 arithmetic

I am trying to make a list of 2x2 matrices whose entries are all possible permutations of 0,1,2 and det=1 mod 2 arithmetic. First I tried to create a Table like this ...
2
votes
3answers
446 views

MatrixForm explanation as why row extract is displayed as a column?

I have a 5 x 5 matrix: cdsSpread5yrs = But after doing a row extract, why is it displaying as a column? ...
4
votes
2answers
2k views

How to make a matrix of derivatives? [duplicate]

For example I can construct: row1 = D[f(x,y),x,#]&/@{x,y} row2 = D[f(x,y),x,#]&/@{x,y} then: ...
0
votes
2answers
1k views
-2
votes
2answers
356 views

Mathematica not assigning variable correctly

So I have been fiddling with this the last hour and I just can't get it to work. I have 3 matrices of the same size which contain nothing but 0's in a list, I also have 3 matrices of the same size (...
6
votes
1answer
290 views

Calculations after NumberForm [duplicate]

As specified in documentation center the functions AccountingForm, NumberForm, etc. are useful only to display numbers in ...
2
votes
1answer
706 views

Change of basis in Mathematica

I'm trying to set up a change of basis matrix from the base V -> W with the RowReduce function that's built into Mathematica. I am then supposed to verify the result by taking the product of the ...
3
votes
2answers
108 views

How do Forms affect the interpretation of Expressions?

Below are three formats for representing an undirected edge between vertices a and b: ...
2
votes
2answers
126 views

Symbolic manipulation of matrix elements [closed]

Can Mathematica compute matrix multiplications/additions symplifying them by a defined set of rules? For example if I have the rules $ bc=x, ac=z, ze=w $ and give Mathematica the expression $$ \begin{...
2
votes
4answers
246 views

Dot product result has wrong dimension [closed]

I'm doing a small project and I've encountered a problem while using Mathematica. I should mention that I'm kinda new to this software, so maybe it's just something I haven't grasped yet. Anyway, I ...
2
votes
1answer
157 views

Revert FullForm back to “normal”

I am trying to find the function that converts the result of FullForm back into a standard pretty looking output. Here is what I mean: ...
2
votes
2answers
85 views

Elements Replacement

Please I need help on how to replace elements in a matrix with another elements. For example, I have a (5,5) matrix, and I like to replace elements from All rows and column 3 to 5, with zero. such ...
0
votes
1answer
231 views

Creating Matrix,Inverted and Upper Triangulate inside Module

I was trying to fit this into a module but I didn't have any luck. And for some reason it won't Inverse the Matrix. Here's the code: Input: ...

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