include/nrjac.h

   1 /*
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   9  *                        VERSION 3.2.0
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  13  * check out http://www.gromacs.org for more information.
  14
  15  * This program is free software; you can redistribute it and/or
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  35
  36 #ifndef _nrjac_h
  37 #define _nrjac_h
  38
  39 #ifdef HAVE_CONFIG_H
  40 #include <config.h>
  41 #endif
  42
  43 extern void jacobi(double **a,int n,double d[],double **v,int *nrot);
  44 /*
  45  * real   **omega = input matrix a[0..n-1][0..n-1] must be symmetric
  46  * int     natoms = number of rows and columns
  47  * real      NULL = d[0]..d[n-1] are the eigenvalues of a[][]
  48  * real       **v = v[0..n-1][0..n-1] the eigenvectors:
  49  *                                    v[i][j] is component i of vector j
  50  * int      *irot = number of jacobi rotations
  51  */
  52
  53 int m_inv_gen(real **m,int n,real **minv);
  54 /* Produces minv, a generalized inverse of m.
  55  * Inversion is done via diagonalization,
  56  * eigenvalues smaller than 1e-6 times the average diagonal element
  57  * are assumed to be zero.
  58  * For zero eigenvalues 1/eigenvalue is set to zero for the inverse matrix.
  59  * Returns the number of zero eigenvalues.
  60  */
  61 #endif