All Questions
8 questions
3
votes
0
answers
188
views
Implementation of an algorithm for simultaneous diagonalization
I am trying to write an implementation of an algorithm for the simultaneous diagonalization of two matrices (which are assumed to be simultaneously diagonalizable). However, the algorithm does not ...
- 316
0
votes
2
answers
1k
views
Python numpy matrix multiplication mismatch in core dimension
I am trying to matrix multiply a 2x2 matrix with a 2x1 matrix. Both matrices have entries which are linspaces such that the resulting 2x1 matrix gives me a value for each value of the linspace.
I get ...
0
votes
1
answer
435
views
Eigenvalue decomposition for a very huge matrix of medical images(such as the pixel physical coordinates of CT images)
I am trying to do eigenvalue decomposition for a huge matrix which size is more than 788000 * 788000 for medical image analysis. The matrix is not sparse and every element in the matrix has a real ...
1
vote
0
answers
148
views
Least positive eigenvalue of a Laplacian matrix
To calculate the eigenvalues of a Laplacian matrix, I used the function numpy.linalg.eig. The least positive eigenvalue I obtained was 2.6645352591003757e-15. What is wrong in the calculation? Is it ...
- 51
0
votes
1
answer
414
views
Determinant of a jacobian matriz using finite differences in python
I am trying to calculate the determinant of the Jacobian matrix and evaluating when that determinant is zero from the functions x and y. I am trying to implement the simple method of finite ...
- 121
0
votes
1
answer
720
views
Numerical solving of overdetermined, nonlinear equation system in Python
Here's a minimal example of my problem - solved with scipy.optimize.leastsq
from scipy.optimize import leastsq
from numpy import array, exp, sin, cos
def MatrixFun(x, *par):
a, b, c, d = par
...
- 117
1
vote
1
answer
810
views
Eigenvectors in Numpy: Very bad numerics? Did I do something wrong?
For some calculations I need an eigenvalue decomposition. Now I tried to evaluate the functions of numpy and noticed that there is a very bad behavior! Look at this:
import numpy as np
N = 3
A = np....
- 6,854
4
votes
5
answers
21k
views
Code to solve determinant using Python without using scipy.linalg.det
Description(this is a hwk question):
I am not sure where to start here. I plan to use Laplace's Expansion but I am not sure how to implement it for nxn matrices. Any help would be appreciated.
Note:...
