All Questions

Tagged with
Filter by
Sorted by
Tagged with
8
votes
0answers
210 views

DEigenvalues and NDEigenvalues return different values

In the following example, DEigenvalues and NDEigenvalues return different results despite having identical arguments. Does anyone know why? (I use Mathematica 11.3) ...
34
votes
2answers
821 views

Eigenvalues broken in Version 12.0

Bug introduced in 12.0. The following code calculates the eigenvalues of a certain complex matrix, which come in pairs of opposite complex numbers. Therefore one can check whether the sum of all ...
6
votes
0answers
63 views

Where is the mistake in computing the particular eigenvector of the following DFT Matrix?

I have the following matrix (the DFT Matrix for N = 3) $$W = \frac{1}{\sqrt{3}}\begin{pmatrix} 1 & 1 & 1 \\ 1 & e^{-\frac{i 2 \pi}{3} } & e^{\frac{i 2 \pi}{3} } \\ 1 & e^{\frac{...
32
votes
1answer
1k views

Complex eigenvalues from a sparse Hermitian matrix

Bug introduced in 9.0 or earlier and persisting through 12.0. I notice in the following example that wrong complex eigenvalues are resulted if calculating from a Hermitian sparse matrix, which should ...
6
votes
2answers
187 views

Unable to evaluate Eigenvalues and Eigenvectors for a matrix

I have the following 3X3 matrix M and I wish to find its eigenvectors and eigenvalues ...
15
votes
0answers
438 views

Wrong eigenvalues from a sparse matrix

Bug introduced after 5.0, in or before 8.0 and persisting through 12.0. I notice in the following example that wrong smallest 2 eigenvalues are resulted if calculating from a sparse matrix. But it ...
22
votes
1answer
1k views

Eigenvalues broken in 11.2?

Bug introduced in 11.1.0 and fixed in 11.3.0 The code ...
5
votes
0answers
77 views

Bug for Cubics -> True in Eigenvalues?

Let's consider the simple code ...
4
votes
1answer
303 views

Plotting eigenvalues with different colours

Bug introduced in version 11 I would like to plot all the eigenvalues (functions of Bz) of a matrix in the same plot, so as for Mathematica to understand that they are different functions and to plot ...
7
votes
2answers
663 views

Calculating smallest eigenvalues by real part using Arnoldi method

Bug introduced in 8.0 or earlier and persisting through 11.3 According to the documentation, Eigenvalues[m,k] gives the first ...