add numerical recipes library

lib/nr/k_and_r/recipes/rlftfrag.c

@@ -0,0 +1,86 @@
+
+#include "nrutil.h"
+#define N2 256
+#define N3 256
+
+main()		/* example1 */
+{
+	void rlft3();
+	float ***data, **speq;
+
+	data=f3tensor(1,1,1,N2,1,N3);
+	speq=matrix(1,1,1,2*N2);
+	rlft3(data,speq,1,N2,N3,1);
+	rlft3(data,speq,1,N2,N3,-1);
+	free_matrix(speq,1,1,1,2*N2);
+	free_f3tensor(data,1,1,1,N2,1,N3);
+	return 0;
+}
+#undef N3
+#undef N2
+
+#define N1 32
+#define N2 64
+#define N3 16
+
+main()		/* example2 */
+{
+	void rlft3();
+	int j;
+	float ***data,**speq;
+
+	data=f3tensor(1,N1,1,N2,1,N3);
+	speq=matrix(1,N1,1,2*N2);
+	rlft3(data,speq,N1,N2,N3,1);
+	free_matrix(speq,1,N1,1,2*N2);
+	free_f3tensor(data,1,N1,1,N2,1,N3);
+	return 0;
+}
+#undef N1
+#undef N2
+#undef N3
+
+#define N 32
+
+main()		/* example3 */
+{
+	void rlft3();
+	int j;
+	float fac,r,i,***data1,***data2,**speq1,**speq2,*sp1,*sp2;
+
+	data1=f3tensor(1,N,1,N,1,N);
+	data2=f3tensor(1,N,1,N,1,N);
+	speq1=matrix(1,N,1,2*N);
+	speq2=matrix(1,N,1,2*N);
+
+	rlft3(data1,speq1,N,N,N,1);
+	rlft3(data2,speq2,N,N,N,1);
+	fac=2.0/(N*N*N);
+	sp1 = &data1[1][1][1];
+	sp2 = &data2[1][1][1];
+	for (j=1;j<=N*N*N/2;j++) {
+		r = sp1[0]*sp2[0] - sp1[1]*sp2[1];
+		i = sp1[0]*sp2[1] + sp1[1]*sp2[0];
+		sp1[0] = fac*r;
+		sp1[1] = fac*i;
+		sp1 += 2;
+		sp2 += 2;
+	}
+	sp1 = &speq1[1][1];
+	sp2 = &speq2[1][1];
+	for (j=1;j<=N*N;j++) {
+		r = sp1[0]*sp2[0] - sp1[1]*sp2[1];
+		i = sp1[0]*sp2[1] + sp1[1]*sp2[0];
+		sp1[0] = fac*r;
+		sp1[1] = fac*i;
+		sp1 += 2;
+		sp2 += 2;
+	}
+	rlft3(data1,speq1,N,N,N,-1);
+	free_matrix(speq2,1,N,1,2*N);
+	free_matrix(speq1,1,N,1,2*N);
+	free_f3tensor(data2,1,N,1,N,1,N);
+	free_f3tensor(data1,1,N,1,N,1,N);
+	return 0;
+}
+#undef N