Manuals/calci/CHOLESKY

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CHOLESKY(arr)


  • is the array of numeric elements

Description

  • This function gives the value of Cholesky factorization.
  • It is called Cholesky Decomposition or Cholesky Factorization.
  • The Cholesky Factorization is only defined for symmetric or Hermitian positive definite matrices.
  • Every positive definite matrix A can be factored as   =  

where

  is lower triangular with positive diagonal elements
  is is the conjugate transpose value of  
  • Every Hermitian positive-definite matrix (and thus also every real-valued symmetric positive-definite matrix) has a unique Cholesky decomposition.
  • Here  ,   is set of values to find the factorization value.
  • Partition matrices in as   =   (Please take the description from http://www.seas.ucla.edu/~vandenbe/103/lectures/chol.pdf )

ZOS Section

Examples

CHOLESKY([[16,32,12],[12, 18, 0],[ -5, 0, 11]])

Result
4 0 0
3 3 0
-1.25 1.25 2.80624

CHOLESKY([[25, 15, -5],[15, 18, 0],[ -5, 0, 11]])

Result
5 0 0
3 3 0
-1 1 3

See Also