// This generates a circle. d = 2.
#include <math.h>
#include "l.h"
#define vc 360
R a[vc][2]; short l[vc][2];
bp g2(){
  R const tpi = 2.*3.1415926535897932385;
  {int j=vc; while(j--) {
     a[j][0] = cos(j*tpi/vc); a[j][1] = sin(j*tpi/vc);
     l[j][0] = j; l[j][1] = j+1;}
   l[vc-1][1] = 0;}
return (bp){2, vc, (R*)a, vc,  (short*)l};}

static R wh[] = {1, -1}; static short c[] = {0, 1};
bp g1(){return (bp){1, 2, wh, 2, c};}

// routine gx returns a zero brane with a boundary.
// This is helpful in debugging.
bp gx(){return (bp){1, 1, wh+1, 1, c};}