/*** Statistical computation stuff.  **/

double erfcc(double x);
double erf(double x);
int calcweight(long pfreqs[AANUM][POSNUM],
	       long pfreqp[AANUM][AANUM][POSNUM][POSNUM],
	       double gprobs[NUM_RES_TYPE],
	       double gprobp[NUM_RES_TYPE][NUM_RES_TYPE][POSNUM],
	       double weights[AANUM][POSNUM],
	       double weightp[AANUM][AANUM][POSNUM][POSNUM],
	       long totals[POSNUM],
	       long totalp[POSNUM][POSNUM],
	       FILE *weight_file);


void combine_many_weight(int current_table);
void calc_distance_weights(double dist_weight[POSNUM]);
double sigma(double x, int power, double middle);