The matrix tag has no wiki summary.
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1answer
32 views
matlab set center of output figure to [0 0 0]
I have a few set of data of three dimensional matrices, n x 3 with x, y and z coordinates.
I viewed the matrices in the figure window.
...
3
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2answers
73 views
how can a 2-d fft be constructed to an equivalent matrix?
When I use the cvx matlab toolbox, I met a puzzled problem. The function of fft (or dct, wavelet, etc.) cannot be recognized by the type of 'cvx'. For the 1-d fft, it can be constructed to an ...
2
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2answers
66 views
Matlab element within ranges and distance between two points
I have a 53534x3 matrix with x, y and z coordinates.
I want to find the element of matrix within ranges as follows:
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0
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0answers
37 views
ZGETRF and ZGETRS from MKL - zgetrf fails and still zgetrs works?
please can you help me with my MKL problem?
I have a big matrix - system of equations, so I have the linear problem
Ax=b
and I know the A matrix and b vector. I'm using MKL to solve this system. The ...
3
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2answers
64 views
Reordering sparse matrices in computational science
On page 3 of this document, there are some matrix forms for sparse matrices. I wonder if there are other forms used in computational problems encountered in physics, chemistry, etc., so that ...
2
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1answer
49 views
Calculate 3x3 matrix to give lowest difference for data set
I'm building an application where I need to compare found data with the actual data it should be.
I have 5 sets of data, each with 3 variables a,b,c.
Let matrix A be a 3x1 matrix with data a,b,c ...
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0answers
64 views
Marker and Cell Method (MAC) - STOKES FLOW - boundaries?
please can you help me with my problem with Stokes flow written using Marker and cell method (MAC)? I need only to solve the eq. of continuity + momentum eq. for a given condition (steady state). I ...
2
votes
1answer
90 views
Singular matrix - but SVD works - what does the eigenvalues mean? Find I the “dependent” lines?
please can I ask a bit stupid question? I have a complex matrix A as a set of equations. I wanted to find the solution of Ax=b where b is vector of right-hand side. So I have called zgetrf on A (does ...
3
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2answers
86 views
LAPACK - singular matrixes - what does the positive integer info mean?
please can you help me with my code - I use Lapack to solve complex matrix (quite biq) and do it in two steps: I call zgetrf (LU factorization) and then ...
6
votes
1answer
180 views
Wrong Result QR decomposition with Pivoting in LAPACK
I am trying to use LAPACK geqp3 function for QR decomposition with pivoting but result is wrong. I tried almost two days but can't figure out the problem. I compared the result with Matlab and Python ...
9
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1answer
146 views
Solving a simple Ax=b system in parallel with PETSc
I am new to the PETSc package.
I have a ~4000x4000 matrix A in matrix-market format and I want to get PETSc to solve this using multiple processors.
I know how to solve the system on a single ...
