#include <math.h>float bessi1(float x){	float ax,ans;	double y;	if ((ax=fabs(x)) < 3.75) {		y=x/3.75;		y*=y;		ans=ax*(0.5+y*(0.87890594+y*(0.51498869+y*(0.15084934			+y*(0.2658733e-1+y*(0.301532e-2+y*0.32411e-3))))));	} else {		y=3.75/ax;		ans=0.2282967e-1+y*(-0.2895312e-1+y*(0.1787654e-1			-y*0.420059e-2));		ans=0.39894228+y*(-0.3988024e-1+y*(-0.362018e-2			+y*(0.163801e-2+y*(-0.1031555e-1+y*ans))));		ans *= (exp(ax)/sqrt(ax));	}	return x < 0.0 ? -ans : ans;}