ezinc.c

国外一大学教授讲章

#include "ezinc.h"

/* global variables -- but private to this file */
static double delay, width=0, cdtds;

/* prompt user for source-function width and delay. */
void ezIncInit(Grid *g){

  cdtds = Cdtds;  
  printf("Enter delay: ");
  scanf(" %lf",&delay);
  printf("Enter width: ");
  scanf(" %lf",&width);

  return;
}

/* calculate source function at given time and location */
double ezInc(double time, double location) {
  if (width<=0) {
    fprintf(stderr,
       "ezInc: must call ezIncInit before ezInc.\n"
       "       Width must be positive.\n");
    exit(-1);
  }
  return exp( -pow( (time - delay - location/cdtds)/width, 2) );
}