#ifndef _FDTD1_H         
#define _FDTD1_H         

#include <stdio.h>
#include <stdlib.h>

struct Grid {            
  double *ez;
  double *hy;
  int sizeX;
  int time, maxTime;
  double cdtds;
};

typedef struct Grid Grid;

/* memory allocation macro */
#define ALLOC_1D(PNTR, NUM, TYPE)                              \
    PNTR = (TYPE *)calloc(NUM, sizeof(TYPE));                   \
    if (!PNTR) {                                                \
      perror("ALLOC_1D");                                       \
      fprintf(stderr,                                           \
          "Allocation failed for " #PNTR ".  Terminating...\n");\
      exit(-1);                                                 \
    }

/* macros for accessing arrays and such */
/* NOTE!!!!  Here we assume the Grid structure is g. */
#define Hy(MM)    g->hy[MM]   
#define Ez(MM)    g->ez[MM]   
#define SizeX     g->sizeX    
#define Time      g->time
#define MaxTime   g->maxTime
#define Cdtds     g->cdtds    

#endif  /* matches #ifndef _FDTD1_H */