extern "C"{/* functions from part_func.c */float  pf_fold(char *sequence, char *structure);/* calculate partition function and base pair probabilities */void   init_pf_fold(int length);    /* allocate space for pf_fold() */void   free_pf_arrays(void);        /* free arrays from pf_fold() */void   update_pf_params(int length); /*recalculate energy parameters */char   bppm_symbol(float *x);   /* string representation of structure */double mean_bp_dist(int length); /* mean pair distance of ensemble */}