Skip to content
/ irlbpy Public

Truncated SVD by implicitly restarted Lanczos bidiagonalization for Python Numpy

License

Notifications You must be signed in to change notification settings

bwlewis/irlbpy

Folders and files

NameName
Last commit message
Last commit date

Latest commit

 

History

34 Commits
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

Repository files navigation

irlbpy

Truncated SVD by implicitly restarted Lanczos bidiagonalization for Numpy!

irlb: A fast and memory-efficient method for estimating a few largest signular values and corresponding singular vectors of very large matrices.

Adapted from the algorithm by Jim Baglama and Lothar Reichel: Augmented Implicitly Restarted Lanczos Bidiagonalization Methods, J. Baglama and L. Reichel, SIAM J. Sci. Comput. 2005.

Installation:

There are several options for installing the irlbpy package. The easiest is to simply pip install the code (either into your system site-packages or virtualenv with the command:

pip install -e git+https://github.com/bwlewis/irlbpy.git#egg=irlb

Otherwise, if you have downloaded the code you can install the package locally by executing the following commands from the project's home directory:

python setup.py sdist
pip install dist/irlbpy-0.1.0.tar.gz

Usage:

S = irlb(A, n, [tol=0.0001 [, maxit=50]])

Where, A is a double-precision-valued matrix, n is the number of singular values and corresponding singular values to compute, tol is an optional convergence tolerance parameter that controls the accuracy of the estimated singular values, and maxit is an optional limit on the maximum number of Lanczos iterations.

The returned triple S contains the matrix of left singular vectors, a vector of singular values, and the matrix of right singular vectors, respectively, such that:

A.dot(S[2]) - S[0]*S[1]

is small.

About

Truncated SVD by implicitly restarted Lanczos bidiagonalization for Python Numpy

Resources

License

Stars

Watchers

Forks

Releases

No releases published

Packages

No packages published

Contributors 3

  •  
  •  
  •