hpsort.c
3b4412d782eflammm-master-deprecated

hpsort.c
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			/* Numerical Recipes heap sort, modified to be like C library qsort */

			/* accepts arbitrary objects to be sorted, user provides compare function
			this routine sorts a F77-style array indexed from 1-n
			thus you MUST call it from C with hpsort(ra-1, ) to offset C ptr by -1
			also added multiply-array-index-by-size to enable arbitrary objects
			*/

			#include <stdlib.h>
			#include <string.h>

			void hpsort(char *ra, int n, int size,
			int (cmp)(const void , const void *))
			{
			unsigned long i,ir,j,l;
			char *rra;

			if (n < 2) return;
			l = (n >> 1)+1;
			ir = n;
			rra = (char *) malloc(size);
			for (;;) {
			if (l > 1) {
			memcpy(rra,&ra[(--l)*size],size);
			} else {
			memcpy(rra,&ra[ir*size],size);
			memcpy(&ra[irsize],&ra[1size],size);
			if (--ir == 1) {
			memcpy(&ra[1*size],rra,size);
			break;
			}
			}
			i = l;
			j = l+l;
			while (j <= ir) {
			if (j < ir && (cmp)(&ra[jsize],&ra[(j+1)*size]) < 0) j++;
			if ((cmp)(rra,&ra[jsize]) < 0) {
			memcpy(&ra[isize],&ra[jsize],size);
			i = j;
			j <<= 1;
			} else j = ir+1;
			}
			memcpy(&ra[i*size],rra,size);
			}
			free(rra);
			}