MathGroup Archive 2012

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: JordanDecompose[]

  • To: mathgroup at
  • Subject: [mg124125] Re: JordanDecompose[]
  • From: danl at
  • Date: Tue, 10 Jan 2012 05:57:55 -0500 (EST)
  • Delivered-to:
  • References: <je3vti$eeh$> <je6e5h$q7b$> <jee7pc$cjq$>
  • Reply-to: comp.soft-sys.math.mathematica at

I should have made that clear. The [...] referred by name to a function in 
the code, not a reference from the literature. I did not want to put internal function names in my post. That function handles the case where the matrix is nonderogatory. More specifically, it handles all eigenvalues that have geometric multiplicity of 1 (I think it also handles the simple case where gemoetric multiplicity = algebraic multiplicity).

The algorithm is not a proprietary secret. I simply cannot find a reference in the literature that seems to describe it. All I have is old lecture notes, if indeed I still have those.

There is something slightly similar, I think, in the text Linear Algebra by Charles Curtis. Itworks out the rational canonical form, then notes that this gives the Jordan decomposition in the special case where we work over the algebraic closure of the matrix coefficients field. Also I think there may be something similar in the algebra text by Dummit and Foote.

Daniel Lichtblau
Wolfram Research

  • Prev by Date: Graphics bounding box in source coordinates?
  • Next by Date: Question about typesetting
  • Previous by thread: Re: JordanDecompose[]
  • Next by thread: DirectoryStack[] not showing top directory stack item