add numerical recipes library

lib/nr/ansi/examples/xhpsel.c

@@ -0,0 +1,41 @@
+
+/* Driver for routine hpsel */
+
+#include <stdio.h>
+#include <stdlib.h>
+#define NRANSI
+#include "nr.h"
+#include "nrutil.h"
+
+#define MAXSTR 80
+#define NP 100
+
+int main(void)
+{
+	char txt[MAXSTR];
+	unsigned long i,k;
+	float *a,*heap,check;
+	FILE *fp;
+
+	a=vector(1,NP);
+	heap=vector(1,NP);
+	if ((fp = fopen("tarray.dat","r")) == NULL)
+		nrerror("Data file tarray.dat not found\n");
+	fgets(txt,MAXSTR,fp);
+	for (i=1;i<=NP;i++) fscanf(fp,"%f",&a[i]);
+	fclose(fp);
+	for (;;) {
+		printf("Input k\n");
+		if (scanf("%lu",&k) == EOF) break;
+		hpsel(k,NP,a,heap);
+		check=select(NP+1-k,NP,a);
+		printf("heap[1], check= %6.2f %6.2f\n",heap[1],check);
+		printf("heap of numbers of size %lu\n",k);
+		for (i=1;i<=k;i++) printf("%lu   %6.2f\n",i,heap[i]);
+	}
+	free_vector(heap,1,NP);
+	free_vector(a,1,NP);
+	printf("Normal completion\n");
+	return 0;
+}
+#undef NRANSI