text: #ifndef agile_nummeths_header
  #define agile_nummeths_header
  
  int interpol(const double* x, const double* fx, int n, double* z, double* pz, int m);
  void lsqe(const double* x, const double* y, int n, double* b1, double* b0);
  int root(double(*f)(double), double(*g)(double), double* x, int* n, double delta);
  
  void test_agile_nummeths();
  
  #endif
  