public int	historicalNumParams(int type){ 
	
		switch (type) {
		
		case HE_POP_SIZE:
			return 1;
		case HE_POP_SIZE_EXP:
		  return 3; /* end_gen, start_size, end_size */
		case HE_BOTTLENECK:
			return 1;
		case HE_ADMIX:
			return 1;
		case HE_MIGRATION:
			return 1;
		case HE_SPLIT:
			return 0;
		case HE_SWEEP:
			return 3;
		}
		 
		return 0;
	}