sin.txt

编译原理的一个课程设计

double sin(double d)
{
  int signal=1;
  if(d<0)
  {
    signal=-1;
    d=-d;
  }
  double Dpi=6.2831853071795865;
  while(d>=Dpi)d=d-Dpi;
  double r,t;   //变量的初始值为0
  int i=1,j;
  while(i<20)
  {
    t=1;
    j=1;
    while(j<=i)
    {
      t=t*d/j;
      j=j+1;
    }
    // t=pow(d,i)/i!
    if(i%4==1)
      r=r+t;
    else
      r=r-t;
    i=i+2;
  }
  return r*signal;
}

void main()
{
  double d=1;
  while(1==1)
  {
    input d;
    if(d<0.0000001 && d>-0.0000001)
      break;
    output "sin( ",d," ) = ",sin(d),"\n";
  }
}