Opened 7 years ago

Closed 7 years ago

Last modified 7 years ago

#1430 closed defect (fixed)

[with spkg] sparse eigenvalues and splines

Reported by: jkantor Owned by: was
Priority: major Milestone: sage-2.9
Component: packages: standard Keywords:
Cc: Merged in:
Authors: Reviewers:
Report Upstream: Work issues:
Branch: Commit:
Dependencies: Stopgaps:

Description

scipy has a sandbox directory with experimental or code in development. One of the packages is an arpack wrapper which computes eigenvalues of sparse matrices. matlab uses this in its eigs command. Although the arpack wrapper is not completely finished, it has useful functionality, and since this has been requested multiple times I think including it is good, it will also maybe spur some people to take the wrapper the last mile (me probably).

Also included is a wrapper of fitpack which has some spline functions (bivariate spline, etc).

http://sage.math.washington.edu/home/jkantor/spkgs/scipy_sandbox.spkg

The following shows how to compute the smallest five eigenvalues (in magnitude) of a 2000x2000 matrix

import arpack
from scipy import sparse
m=sparse.csc_matrix(random_matrix(RDF,2000,2000,density=.02).numpy())
e,v=arpack.eigen(m,5)

Change History (4)

comment:2 Changed 7 years ago by mabshoff

  • Resolution set to fixed
  • Status changed from new to closed

Merged in 2.9.alpha6.

comment:3 Changed 7 years ago by jkantor

new patch, makes the doctest more stable (hopefully) http://sage.math.washington.edu/home/jkantor/spkgs/arpack_doctest_2.patch

(apply after applying the first one)

comment:4 Changed 7 years ago by mabshoff

I apply arpack_doctest_2.patch to 2.9.rc0.

Cheers,

Michael

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