NAME

PDL::Slatec -- PDL interface to the slatec numerical programming library


DESCRIPTION

This module serves the dual purpose of showing how to interface PDL to an external library and providing various functions to interface to the slatec library. In due time, reasonable perl functions will be provided to take advantage of all the library but currently we only have


SYNOPSIS

 use PDL::Slatec;


FUNCTIONS


eigsys

Eigenvalues and eigenvectors of a real positive definite symmetric matrix.

($eigvals,$eigvecs) = eigsys($mat)

Note: this function should be extended to calculate only eigenvalues if called in scalar context!


matinv

Inverse of a square matrix

 ($inv) = matinv($mat)

Using this library requires a fortran compiler. The source for the routines is provided for convenience.


AUTHOR

Copyright (C) 1997 Tuomas J. Lukka. All rights reserved. There is no warranty. You are allowed to redistribute this software / documentation under certain conditions. For details, see the file COPYING in the PDL distribution. If this file is separated from the PDL distribution, the copyright notice should be included in the file.


FUNCTIONS


svdc

  Signature: (x(n,p);[o]s(p);[o]e(p);[o]u(n,p);[o]v(p,p);[o]work(n);int job();int [o]info())

singular value decomposition of a matrix


poco

  Signature: (a(n,n);rcond();[o]z(n);int [o]info())

Factor a real symmetric positive definite matrix and estimate the condition number of the matrix.


geco

  Signature: (a(n,n);int [o]ipvt(n);[o]rcond();[o]z(n))

Factor a matrix using Gaussian elimination and estimate the condition number of the matrix.


gefa

  Signature: (a(n,n);int [o]ipvt(n);int [o]info())

Factor a matrix using Gaussian elimination.


podi

  Signature: (a(n,n);[o]det(two=2);int job())

Compute the determinant and inverse of a certain real symmetric positive definite matrix using the factors computed by SPOCO, SPOFA or SQRDC.


gedi

  Signature: (a(n,n);int [o]ipvt(n);[o]det(two=2);[o]work(n);int job())

Compute the determinant and inverse of a matrix using the factors computed by SGECO or SGEFA.


gesl

  Signature: (a(lda,n);int ipvt(n);b(n);int job())

Solve the real system A*X=B or TRANS(A)*X=B using the factors computed by DGECO or DGEFA


rs

  Signature: (a(n,n);[o]w(n);int matz();[o]z(n,n);[t]fvone(n);[t]fvtwo(n);int [o]ierr())

This subroutine calls the recommended sequence of subroutines from the eigensystem subroutine package (EISPACK) to find the eigenvalues and eigenvectors (if desired) of a REAL SYMMETRIC matrix.


ezffti

  Signature: (int n();[o]wsave(foo))

Subroutine EZFFTI initializes the work array WSAVE which is used in both EZFFTF and EZFFTB. The prime factorization of N together with a tabulation of the trigonometric functions are computed and stored in WSAVE.


ezfftf

  Signature: (r(n);[o]azero();[o]a(n);[o]b(n);wsave(foo))

info not available


ezfftb

  Signature: ([o]r(n);azero();a(n);b(n);wsave(foo))

info not available