#include "fdtd-macro-tmz.h"
#include "fdtd-alloc1.h"
#include <math.h>

void gridInit(Grid *g) {
  double imp0 = 377.0;
  int mm, nn;

  Type = tmZGrid;                          
  SizeX = 101;             // x size of domain
  SizeY = 81;              // y size of domain
  MaxTime = 300;           // duration of simulation
  Cdtds = 1.0 / sqrt(2.0); // Courant number

  ALLOC_2D(g->hx,   SizeX, SizeY - 1, double);  
  ALLOC_2D(g->chxh, SizeX, SizeY - 1, double);
  ALLOC_2D(g->chxe, SizeX, SizeY - 1, double);
  ALLOC_2D(g->hy,   SizeX - 1, SizeY, double);
  ALLOC_2D(g->chyh, SizeX - 1, SizeY, double);
  ALLOC_2D(g->chye, SizeX - 1, SizeY, double);
  ALLOC_2D(g->ez,   SizeX, SizeY, double);
  ALLOC_2D(g->ceze, SizeX, SizeY, double);
  ALLOC_2D(g->cezh, SizeX, SizeY, double);    
 
  /* set electric-field update coefficients */
  for (mm = 0; mm < SizeX; mm++)
    for (nn = 0; nn < SizeY; nn++) {
      Ceze(mm, nn) = 1.0;
      Cezh(mm, nn) = Cdtds * imp0;
    }

  /* set magnetic-field update coefficients */
  for (mm = 0; mm < SizeX; mm++)
    for (nn = 0; nn < SizeY - 1; nn++) {
      Chxh(mm, nn) = 1.0;
      Chxe(mm, nn) = Cdtds / imp0;
    }

  for (mm = 0; mm < SizeX - 1; mm++)
    for (nn = 0; nn < SizeY; nn++) {
      Chyh(mm, nn) = 1.0;
      Chye(mm, nn) = Cdtds / imp0;
    }

  return;
}