Skip to main content

Compute and visualize pseudospectra of matrices (like eigtool)

Project description

# PseudoPy [![Build Status](](

PseudoPy computes and visualizes the pseudospectrum of a matrix. It is a Python version of the original [eigtool]( by Thomas G. Wright. The algorithms used in this package can be found in the book [Spectra and pseudospectra]( by [Nick Trefethen]( and [Mark Embree](

## Example
The pseudospectrum of the Grcar matrix looks like this:

![Pseudospectrum of Grcar matrix](grcar.png)

If no knowledge about the location of the pseudospectrum of the given matrix is available, the following lines of code can be used to obtain an approximation:
from pseudopy import NonnormalAuto, demo
from matplotlib import pyplot
from scipy.linalg import eigvals

# get Grcar matrix
A = demo.grcar(32).todense()

# compute pseudospectrum for the levels of interest between [1e-5, 1]
pseudo = NonnormalAuto(A, 1e-5, 1)

# plot
pseudo.plot([10**k for k in range(-4, 0)], spectrum=eigvals(A))

## Installation
### Dependencies
PseudoPy depends on numpy, scipy, matplotlib and shapely. If you are on Debian/Ubuntu, you can install these dependencies with
sudo apt-get install python-numpy python-scipy python-matplotlib python-shapely

### pip
```pip install pseudopy```

Note that you may need to add `sudo` if you want to install it system-wide.

## License
PseudoPy is free software licensed under the [MIT License](

Project details

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Source Distribution

pseudopy-1.2.5.tar.gz (7.4 kB view hashes)

Uploaded source

Supported by

AWS AWS Cloud computing and Security Sponsor Datadog Datadog Monitoring Fastly Fastly CDN Google Google Download Analytics Microsoft Microsoft PSF Sponsor Pingdom Pingdom Monitoring Sentry Sentry Error logging StatusPage StatusPage Status page