void gpsheading()
{

float x,y,deltalog,deltalat;

deltalog= logd-logc;
deltalat=latd-latc;

x=cos(latd)*sin(deltalog);
y=(cos(latc)*sin(latd))-(sin(latc)*cos(latd)*cos(deltalog));


bearing=(atan2(x,y))*(180/3.14);
Serial.print("bearing");
Serial.println(bearing);


float a,d,c;

a=(((sin(deltalat/2)))*(sin(deltalat/2))) + ((cos(latc))*(cos(latd))* (((sin(deltalog/2)))*(sin(deltalog/2)))  );

c=2*(atan2(sqrt(a),sqrt(1-a)));

d=6371*c; 


//Serial.println(d);

  
}