/* this pair forms the veclib matrix inversion routine pair */
void dgesl(double amat[], 
  long int l, 
  long int n, 
  long int ipiv[], 
  double bvec[], 
  long int job);

void dgeco(double amat[], 
  long int l, 
  long int n, 
  long int ipiv[], 
  double rcond, 
  double work[]);