add numerical recipes library

lib/nr/k_and_r/recipes/mppi.c

@@ -0,0 +1,66 @@
+
+#include <stdio.h>
+#include "nrutil.h"
+#define IAOFF 48
+
+void mppi(n)
+int n;
+{
+	void mp2dfr(),mpadd(),mpinv(),mplsh(),mpmov(),mpmul(),mpsdv(),mpsqrt();
+	int ir,j,m;
+	unsigned char mm,*x,*y,*sx,*sxi,*t,*s,*pi;
+
+	x=cvector(1,n+1);
+	y=cvector(1,n<<1);
+	sx=cvector(1,n);
+	sxi=cvector(1,n);
+	t=cvector(1,n<<1);
+	s=cvector(1,3*n);
+	pi=cvector(1,n+1);
+	t[1]=2;
+	for (j=2;j<=n;j++) t[j]=0;
+	mpsqrt(x,x,t,n,n);
+	mpadd(pi,t,x,n);
+	mplsh(pi,n);
+	mpsqrt(sx,sxi,x,n,n);
+	mpmov(y,sx,n);
+	for (;;) {
+		mpadd(x,sx,sxi,n);
+		mpsdv(x,&x[1],n,2,&ir);
+		mpsqrt(sx,sxi,x,n,n);
+		mpmul(t,y,sx,n,n);
+		mpadd(&t[1],&t[1],sxi,n);
+		x[1]++;
+		y[1]++;
+		mpinv(s,y,n,n);
+		mpmul(y,&t[2],s,n,n);
+		mplsh(y,n);
+		mpmul(t,x,s,n,n);
+		mm=t[2]-1;
+		for (j=3;j<=n;j++) {
+			if (t[j] != mm) break;
+		}
+		m=t[n+1]-mm;
+		if (j <= n || m > 1 || m < -1) {
+				mpmul(s,pi,&t[1],n,n);
+				mpmov(pi,&s[1],n);
+				continue;
+		}
+		printf("pi=\n");
+		s[1]=pi[1]+IAOFF;
+		s[2]='.';
+		m=mm;
+		mp2dfr(&pi[1],&s[2],n-1,&m);
+		s[m+3]=0;
+		printf(" %64s\n",&s[1]);
+		free_cvector(pi,1,n+1);
+		free_cvector(s,1,3*n);
+		free_cvector(t,1,n<<1);
+		free_cvector(sxi,1,n);
+		free_cvector(sx,1,n);
+		free_cvector(y,1,n<<1);
+		free_cvector(x,1,n+1);
+		return;
+	}
+}
+#undef IAOFF